Washington Naval Treaty, 1922

CONFERENCE ON THE LIMITATION OF ARMAMENT, WASHINGTON, NOVEMBER 12 1921-FEBRUARY 6, 1922.

Treaty Between the United States of America, the British Empire, France, Italy, and Japan, Signed at Washington, February 6, 1922. [41] The United States of America, the British Empire, France, Italy and Japan:

Desiring to contribute to the maintenance of the general peace, and to reduce the burdens of competition in armament;

[41] In English and French; French text not printed. Ratification advised by the Senate, Mar. 29, 1922; ratified by the President, June 9, 1923; ratifications deposited with the Government of the United States, Aug. 17, 1923; proclaimed, Aug. 21, 1923.

Have resolved, with a view to accomplishing these purposes, to conclude a treaty to limit their respective naval armament, and to that end have appointed as their Plenipotentiaries;

The President of the United States of America:
 * Charles Evans Hughes,
 * Henry Cabot Lodge,
 * Oscar W. Underwood,
 * Elihu Root,
 * citizens of the United States;

His Majesty the King of the United Kingdom of Great Britain and Ireland
 * and of the British Dominions beyond the Seas, Emperor of India:
 * The Right Honourable Arthur James Balfour, O. M., M. P.,
 * Lord President of His Privy Council;
 * The Right Honourable Baron Lee of Fareham, G. B. E., K. C. B.,
 * First Lord of His Admiralty;
 * The Right Honourable Sir Auckland Campbell Geddes, K. C. B.,
 * His Ambassador Extraordinary and Plenipotentiary to the United States of America;

and
 * for the Dominion of Canada:
 * The Right Honourable Sir Robert Laird Borden,
 * G. C. M. G., K. C.;


 * for the Commonwealth of Australia:
 * Senator the Right Honourable George Foster Pearce, Minister
 * for Home and Territories;


 * for the Dominion of New Zealand:
 * The Honourable Sir John William Salmond, K. C., Judge of the
 * Supreme Court of New Zealand;


 * for the Union of South Africa:
 * The Right Honourable Arthur James Balfour, O. M., M. P.;


 * for India:
 * The Right Honourable Valingman Sankaranarayana Srinivasa Sastri,
 * Member of the Indian Council of State;

The President of the French Republic:
 * Mr. Albert Sarraut, Deputy, Minister of the Colonies;
 * Mr. Jules J. Jusserand, Ambassador Extraordinary and Plenipotentiary
 * to the United States of America, Grand Cross of the National Order of the Legion of Honour;

His Majesty the King of Italy: 
 * The Honourable Carlo Schanzer, Senator of the Kingdom;
 * The Honourable Vittorio Rolandi Ricci, Senator of the Kingdom, His
 * Ambassador Extraordinary and Plenipotentiary at Washington;
 * The Honourable Luigi Albertini, Senator of the Kingdom;

His Majesty the Emperor of Japan:
 * Baron Tomosaburo Kato, Minister for the Navy, Junii, a member of the
 * First Class of the Imperial Order of the Grand Cordon of the Rising Sun with the Paulownia Flower;
 * Baron Kijuro Shidehara, His Ambassador Extraordinary and
 * Plenipotentiary at Washington, Joshii, a member of the First Class of the Imperial Order of the Rising Sun;
 * Mr. Masanao Hanihara, Vice Minister for Foreign Affairs, Jushii, a member of the Second Class of the Imperial Order of the Rising Sun;

Who, having communicated to each other their respective full powers, found to be in good and due form, have agreed as follows:

Article I
The Contracting Powers agree to limit their respective naval armament as provided in the present Treaty.

Article II
The Contracting Powers may retain respectively the capital ships which are specified in Chapter II, Part 1. On the coming into force of the present Treaty, but subject to the following provisions of this Article, all other capital ships, built or building, of the United States, the British Empire and Japan shall be disposed of as prescribed in Chapter II, Part 2.

In addition to the capital ships specified in Chapter II, Part 1, the United States may complete and retain two ships of the West Virginia class now under construction. On the completion of these two ships, the North Dakota and Delaware, shall be disposed of as prescribed in Chapter II, Part 2.

The British Empire may, in accordance with the replacement table in Chapter II, Part 3, construct two new capital ships not exceeding 35,000 tons (35,560 metric tons) standard displacement each. On the completion of the said two ships the Thunderer, King George V, Ajax and Centurion shall be disposed of as prescribed in Chapter II, Part 2.

Article III
Subject to the provisions of Article II, the Contracting Powers shall abandon their respective capital ship building programs, and no new capital ships shall be constructed or acquired by any of the Contracting Powers except replacement tonnage which may be constructed or acquired as specified in Chapter II, Part 3.

Ships which are replaced in accordance with Chapter II, Part 3, shall be disposed of as prescribed in Part 2 of that Chapter.

Article IV
The total capital ship replacement tonnage of each of the Contracting Powers shall not exceed in standard displacement, for the United States 525,000 tons (533,400 metric tons); for the British Empire 525,000 tons (533,400 metric tons); for France 175,000 tons (177,800 metric tons); for Italy 175,000 tons (177,800 metric tons); for Japan 315,000 tons (320,040 metric tons).

Article V
No capital ship exceeding 35,000 tons (35,560 metric tons) standard displacement shall be acquired by, or constructed by, for, or within the jurisdiction of, any of the Contracting Powers.

Article VI
No capital ship of any of the Contracting Powers shall carry a gun with a calibre in excess of 16 inches (406 millimetres).

Article VII
The total tonnage for aircraft carriers of each of the Contracting Powers shall not exceed in standard displacement, for the United States 135,000 tons (137,160 metric tons); for the British Empire 135,000 tons (137,160 metric tons); for France 60,000 tons (60,960 metric tons); for Italy 60,000 tons (60,960 metric tons); for Japan 81,000 tons (82,296 metric tons).

Article VIII
The replacement of aircraft carriers shall be effected only as prescribed in Chapter II, Part 3, provided, however, that all aircraft carrier tonnage in existence or building on November 12, 1921, shall be considered experimental, and may be replaced, within the total tonnage limit prescribed in Article VII, without regard to its age.

Article IX
No aircraft carrier exceeding 27,000 tons (27,432 metric tons) standard displacement shall be acquired by, or constructed by, for or within the jurisdiction of, any of the Contracting Powers.

However, any of the Contracting Powers may, provided that its total tonnage allowance of aircraft carriers is not thereby exceeded, build not more than two aircraft carriers, each of a tonnage of not more than 33,000 tons (33,528 metric tons) standard displacement, and in order to effect economy any of the Contracting Powers may use for this purpose any two of their ships, whether constructed or in course of construction, which would otherwise be scrapped under the provisions of Article II. The armament of any aircraft carriers exceeding 27,000 tons (27,432 metric tons) standard displacement shall be in accordance with the requirements of Article X, except that the total number of guns to be carried in case any of such guns be of a calibre exceeding 6 inches (152 millimetres), except anti-aircraft guns and guns not exceeding 5 inches (127 millimetres), shall not exceed eight.

Article X
No aircraft carrier of any of the Contracting Powers shall carry a gun with a calibre in excess of 8 inches (203 millimetres). Without prejudice to the provisions of Article IX, if the armament carried includes guns exceeding 6 inches (152 millimetres) in calibre the total number of guns carried, except anti-aircraft guns and guns not exceeding 5 inches (127 millimetres), shall not exceed ten. If alternatively the armament contains no guns exceeding 6 inches (152 millimetres) in calibre, the number of guns is not limited. In either case the number of anti-aircraft guns and of guns not exceeding 5 inches (127 millimetres) is not limited.

Article XI
No vessel of war exceeding 10,000 tons (10,160 metric tons) standard displacement, other than a capital ship or aircraft carrier, shall be acquired by, or constructed by, for, or within the jurisdiction of, any of the Contracting Powers. Vessels not specifically built as fighting ships nor taken in time of peace under government control for fighting purposes, which are employed on fleet duties or as troop transports or in some other way for the purpose of assisting in the prosecution of hostilities otherwise than as fighting ships, shall not be within the limitations of this Article.

Article XII
No vessel of war of any of the Contracting Powers, hereafter laid down, other than a capital ship, shall carry a gun with a calibre in excess of 8 inches (203 millimetres).

Article XIII
Except as provided in Article IX, no ship designated in the present Treaty to be scrapped may be reconverted into a vessel of war.

Article XIV
No preparations shall be made in merchant ships in time of peace for the installation of warlike armaments for the purpose of converting such ships into vessels of war, other than the necessary stiffening of decks for the mounting of guns not exceeding 6 inch (152 millimetres) calibre.

Article XV
No vessel of war constructed within the jurisdiction of any of the Contracting Powers for a non-Contracting Power shall exceed the limitations as to displacement and armament prescribed by the present Treaty for vessels of a similar type which may be constructed by or for any of the Contracting Powers; provided, however, that the displacement for aircraft carriers constructed for a non-Contracting Power shall in no case exceed 27,000 tons (27,432 metric tons) standard displacement.

Article XVI
If the construction of any vessel of war for a non-Contracting Power is undertaken within the jurisdiction of any of the Contracting Powers, such Power shall promptly inform the other Contracting Powers of the date of the signing of the contract and the date on which the keel of the ship is laid; and shall also communicate to them the particulars relating to the ship prescribed in Chapter II, Part 3, Section I (b), (4) and (5).

Article XVII
In the event of a Contracting Power being engaged in war, such Power shall not use as a vessel of war any vessel of war which may be under construction within its jurisdiction for any other Power, or which may have been constructed within its jurisdiction for another Power and not delivered.

Article XVIII
Each of the Contracting Powers undertakes not to dispose by gift, sale or any mode of transfer of any vessel of war in such a manner that such vessel may become a vessel of war in the Navy of any foreign Power.

Article XIX
The United States, the British Empire and Japan agree that the status quo at the time of the signing of the present Treaty, with regard to fortifications and naval bases, shall be maintained in their respective territories and possessions specified hereunder:

(1) The insular possessions which the United States now holds or may hereafter acquire in the Pacific Ocean, except (a) those adjacent to the coast of the United States, Alaska and the Panama Canal Zone, not including the Aleutian Islands, and (b) the Hawaiian Islands;

(2) Hong Kong and the insular possessions which the British Empire now holds or may hereafter acquire in the Pacific Ocean, east of the meridian of 110° east longitude, except (a) those adjacent to the coast of Canada, (b) the Commonwealth of Australia and its Territories, and (c) New Zealand;

(3) The following insular territories and possessions of Japan in the Pacific Ocean, to wit: the Kurile Islands, the Bonin Islands, Amami-Oshima, the Loochoo Islands, Formosa and the Pescadores, and any insular territories or possessions in the Pacific Ocean which Japan may hereafter acquire.

The maintenance of the status quo under the foregoing provisions implies that no new fortifications or naval bases shall be established in the territories and possessions specified; that no measures shall be taken to increase the existing naval facilities for the repair and maintenance of naval forces, and that no increase shall be made in the coast defences of the territories and possessions above specified. This restriction, however, does not preclude such repair and replacement of worn-out weapons and equipment as is customary in naval and military establishments in time of peace.

Article XX
The rules for determining tonnage displacement prescribed in Chapter II, Part 4, shall apply to the ships of each of the Contracting Powers.

PART 1.-Capital Ships Which may Be Retained by the Contracting Powers
In accordance with Article II ships may be retained by each of the Contracting Powers as specified in this Part.

SHIPS WHICH MAY BE RETAINED BY THE UNITED STATES
On the completion of the two ships of the West Virginia class and the scrapping of the North Dakota and Delaware, as provided in Article II, the total tonnage to be retained by the United States will be 525,850 tons.

SHIPS WHICH MAY BE RETAINED BY THE BRITISH EMPIRE
On the completion of the two new ships to be constructed and the scrapping of the Thunderer, King George V, Ajax and Centurion, as provided in Article II, the total tonnage to be retained by the British Empire will be 558,950 tons. Page 255

SHIPS WHICH MAY BE RETAINED BY FRANCE
France may lay down new tonnage in the years 1927, 1929, and 1931, as provided in Part 3, Section II||

SHIPS WHICH MAY BE RETAINED BY ITALY
Italy may lay down new tonnage in the years 1927, 1929, and 1931, as provided in Part 3, Section II||

PART 2.-Rules for Scrapping Vessels of War
The following rules shall be observed for the scrapping of vessels of war which are to be disposed of in accordance with Articles II and III.

I. A vessel to be scrapped must be placed in such condition that it cannot be put to combatant use.

II. This result must be finally effected in any one of the following ways:
 * (a) Permanent sinking of the vessel;
 * (b) Breaking the vessel up. This shall always involve the destruction or removal of all machinery, boilers and armour, and all deck, side and bottom plating;
 * (c) Converting the vessel to target use exclusively. In such case all the provisions of paragraph III of this Part, except sub-paragraph (6), in so far as may be necessary to enable the ship to be used as a mobile target, and except sub-paragraph (7), must be previously complied with. Not more than one capital ship may be retained for this purpose at one time by any of the Contracting Powers.
 * (d) Of the capital ships which would otherwise be scrapped under the present Treaty in or after the year 1931, France and Italy may each retain two sea-going vessels for training purposes exclusively, that is, as gunnery or torpedo schools. The two vessels retained by France shall be of the Jean Bart class, and of those retained by Italy one shall be the Dante Alighieri, the other of the Giulio Cesare class. On retaining these ships for the purpose above stated, France and Italy respectively undertake to remove and destroy their conning-towers, and not to use the said ships as vessels of war

III. (a) Subject to the special exceptions contained in Article IX, when a vessel is due for scrapping, the first stage of scrapping, which consists in rendering a ship incapable of further warlike service, shall be immediately undertaken.

(b) A vessel shall be considered incapable of further warlike service when there shall have been removed and landed, or else destroyed in the ship: (1) All guns and essential portions of guns, fire-control tops and revolving parts of all barbettes and turrets; (2) All machinery for working hydraulic or electric mountings; (3) All fire-control instruments and range-finders; (4) All ammunition, explosives and mines; (5) All torpedoes, warheads and torpedo tubes; (6) All wireless telegraphy installations; (7) The conning tower and all side armour, or alternatively all main propelling machinery; and (8) All landing and flying-off platforms and all other aviation accessories.

IV. The periods in which scrapping of vessels is to be effected are as follows:

(a) In the case of vessels to be scrapped under the first paragraph of Article II, the work of rendering the vessels incapable of further warlike service, in accordance with paragraph III of this Part, shall be completed within six months from the coming into force of the present Treaty, and the scrapping shall be finally effected within eighteen months from such coming into force.

(b) In the case of vessels to be scrapped under the second and third paragraphs of Article II, or under Article III, the work of rendering the vessel incapable of further warlike service in accordance with paragraph III of this Part shall be commenced not later than the date of completion of its successor, and shall be finished within six months from the date of such completion. The vessel shall be finally scrapped, in accordance with paragraph II of this Part, within eighteen months from the date of completion of its successor. If, however, the completion of the new vessel be delayed, then the work of rendering the old vessel incapable of further war-like service in accordance with paragraph III of this Part shall be commenced within four years from the laying of the keel of the new vessel, and shall be finished within six months from the date on which such work was commenced, and the old vessel shall be finally scrapped in accordance with paragraph II of this Part within eighteen months from the date when the work of rendering it incapable of further warlike service was commenced.

PART 3.-Replacement
The replacement of capital ships and aircraft carriers shall take place according to the rules in Section I and the tables in Section II of this Part.

SECTION I.-RULES FOR REPLACEMENT
(a) Capital ships and aircraft carriers twenty years after the date of their completion may, except as otherwise provided in Article VIII and in the tables in Section II of this Part, be replaced by new construction, but within the limits prescribed in Article IV and Article VII. The keels of such new construction may, except as otherwise provided in Article VIII and in the tables in Section II of this Part, be laid down not earlier than seventeen years from the date of completion of the tonnage to be replaced, provided, however, that no capital ship tonnage, with the exception of the ships referred to in the third paragraph of Article II, and the replacement tonnage specifically mentioned in Section II of this Part, shall be laid down until ten years from November 12, 1921.

(b) Each of the Contracting Powers shall communicate promptly to each of the other Contracting Powers the following information:
 * (1) The names of the capital ships and aircraft carriers to be replaced by new construction;
 * (2) The date of governmental authorization of replacement tonnage;
 * (3) The date of laying the keels of replacement tonnage;
 * (4) The standard displacement in tons and metric tons of each new ship to be laid down, and the principal dimensions, namely, length at waterline, extreme beam at or below waterline, mean draft at standard displacement;
 * (5) The date of completion of each new ship and its standard displacement in tons and metric tons, and the principal dimensions, namely, length at waterline, extreme beam at or below waterline, mean draft at standard displacement, at time of completion

(c) In case of loss or accidental destruction of capital ships or aircraft carriers, they may immediately be replaced by new construction subject to the tonnage limits prescribed in Articles IV and VII and in conformity with the other provisions of the present Treaty, the regular replacement program being deemed to be advanced to that extent.

(d) No retained capital ships or aircraft carriers shall be reconstructed except for the purpose of providing means of defense against air and submarine attack, and subject to the following rules: The Contracting Powers may, for that purpose, equip existing tonnage with bulge or blister or anti-air attack deck protection, providing the increase of displacement thus effected does not exceed 3,000 tons (3,048 metric tons) displacement for each ship. No alterations in side armor, in calibre, number or general type of mounting of main armament shall be permitted except:
 * (1) in the case of France and Italy, which countries within the limits allowed for bulge may increase their armor protection and the calibre of the guns now carried on their existing capital ships so as not to exceed 16 inches (406 millimeters) and
 * (2) the British Empire shall be permitted to complete, in the case of the Renown, the alterations to armor that have already been commenced but temporarily suspended.

UNITED STATES
* The United States may retain the Oregon and Illinois, for noncombatant purposes, after complying with the provisions of Part 2, III(b). Note.-A, B, C, D, etc., represent individual capital ships of 35,000 tons standard displacement, laid down and completed in the years specified.
 * 1) Two West Virginia Class.

BRITISH EMPIRE
* The British Empire may retain the Colossus and Collingwood for noncombatant purposes, after complying with the provisions of Part 2, III (b).


 * 1) Two 35,000-ton ships, standard displacement.

Note.-A, B, C, D, etc., represent individual capital ships of 35,000 tons standard displacement, laid down and completed in the years specified.

FRANCE
Note.-France expressly reserves the right of employing the capital ship tonage allotment as she may consider advisable, subject solely to the limitations that the displacement of individual ships should not surpass 35,000 tons, and the total capital ship tonnage should keep within the limits imposed by the present Treaty.

ITALY
Note.-Italy expressly reserves the right of employing the capital ship tonage allotment as she may consider advisable, subject solely to the limitations that the displacement of individual ships should not surpass 35,000 tons, and the total capital ship tonnage should keep within the limits imposed by the present Treaty.

[42] Should read "Guilio Cesare."

JAPAN
* Japan may retain the Shikishima and Asahi for noncombatant purposes, after complying with the provisions of Part 2, III(b).

Note.-A, B, C, D, etc., represent individual capital ships of 35,000 tons standard displacement, laid down and completed in the years specified.

NOTE APPLICABLE TO ALL THE TABLES IN SECTION II The order above prescribed in which ships are to be scrapped is in accordance with their age. It is understood that when replacement begins according to the above tables the order of scrapping in the case of the ships of each of the Contracting Powers may be varied at its option; provided, however, that such Power shall scrap in each year the number of ships above stated.

PART 4.-Definitions
For the purposes of the present Treaty, the following expressions are to be understood in the sense defined in this Part.

CAPITAL SHIP
A capital ship, in the case of ships hereafter built, is defined as a vessel of war, not an aircraft carrier, whose displacement exceeds 10,000 tons (10,160 metric tons) standard displacement, or which carries a gun with a calibre exceeding 8 inches (203 millimetres).

AIRCRAFT CARRIER
An aircraft carrier is defined as a vessel of war with a displacement in excess of 10,000 tons (10,160 metric tons) standard displacement designed for the specific and exclusive purpose of carrying aircraft. It must be so constructed that aircraft can be launched therefrom and landed thereon, and not designed and constructed for carrying a more powerful armament than that allowed to it under Article IX or Article X as the case may be.

STANDARD DISPLACEMENT
The standard displacement of a ship is the displacement of the ship complete, fully manned, engined, and equipped ready for sea, including all armament and ammunition, equipment, outfit, provisions and fresh water for crew, miscellaneous stores and implements of every description that are intended to be carried in war, but without fuel or reserve feed water on board.

The word "ton" in the present Treaty, except in the expression "metric tons", shall be understood to mean the ton of 2240 pounds (1016 kilos).

Vessels now completed shall retain their present ratings of displacement tonnage in accordance with their national system of measurement. However, a Power expressing displacement in metric tons shall be considered for the application of the present Treaty as owning only the equivalent displacement in tons of 2240 pounds.

A vessel completed hereafter shall be rated at its displacement tonnage when in the standard condition defined herein.

Article XXI
If during the term of the present Treaty the requirements of the national security of any Contracting Power in respect of naval defence are, in the opinion of that Power, materially affected by any change of circumstances, the Contracting Powers will, at the request of such Power, meet in conference with a view to the reconsideration of the provisions of the Treaty and its amendment by mutual agreement.

In view of possible technical and scientific developments, the United States, after consultation with the other Contracting Powers, shall arrange for a conference of all the Contracting Powers which shall convene as soon as possible after the expiration of eight years from the coming into force of the present Treaty to consider what changes, if any, in the Treaty may be necessary to meet such developments.

Article XXII
Whenever any Contracting Power shall become engaged in a war which in its opinion affects the naval defence of its national security, such Power may after notice to the other Contracting Powers suspend for the period of hostilities its obligations under the present Treaty other than those under Articles XIII and XVII, provided that such Power shall notify the other Contracting Powers that the emergency is of such a character as to require such suspension.

The remaining Contracting Powers shall in such case consult together with a view to agreement as to what temporary modifications if any should be made in the Treaty as between themselves. Should such consultation not produce agreement, duly made in accordance with the constitutional methods of the respective Powers, any one of said Contracting Powers may, by giving notice to the other Contracting Powers, suspend for the period of hostilities its obligations under the present Treaty, other than those under Articles XIII and XVII.

On the cessation of hostilities the Contracting Powers will meet in conference to consider what modifications, if any, should be made in the provisions of the present Treaty.

Article XXIII
The present Treaty shall remain in force until December 31st, 1936, and in case none of the Contracting Powers shall have given notice two years before that date of its intention to terminate the treaty, it shall continue in force until the expiration of two years from the date on which notice of termination shall be given by one of the Contracting Powers, whereupon the Treaty shall terminate as regards all the Contracting Powers. Such notice shall be communicated in writing to the Government of the United States, which shall immediately transmit a certified copy of the notification to the other Powers and inform them of the date on which it was received. The notice shall be deemed to have been given and shall take effect on that date. In the event of notice of termination being given by the Government of the United States, such notice shall be given to the diplomatic representatives at Washington of the other Contracting Powers, and the notice shall be deemed to have been given and shall take effect on the date of the communication made to the said diplomatic representatives.

Within one year of the date on which a notice of termination by any Power has taken effect, all the Contracting Powers shall meet in conference.

Article XXIV
The present Treaty shall be ratified by the Contracting Powers in accordance with their respective constitutional methods and shall take effect on the date of the deposit of all the ratifications, which shall take place at Washington as soon as possible. The Government of the United States will transmit to the other Contracting Powers a certified copy of the procès-verbal of the deposit of ratifications.

The present Treaty, of which the French and English texts are both authentic, shall remain deposited in the archives of the Government of the United States, and duly certified copies thereof shall be transmitted by that Government to the other Contracting Powers.

IN FAITH WHEREOF the above-named Plenipotentiaries have signed the present Treaty.

DONE at the City of Washington the sixth day of February, One Thousand Nine Hundred and Twenty-Two.
 * [SEAL] CHARLES EVANS HUGHES
 * [SEAL] HENRY CABOT LODGE
 * [SEAL] OSCAR W UNDERWOOD
 * [SEAL] ELIHU ROOT
 * [SEAL] ARTHUR JAMES BALFOUR
 * [SEAL] LEE OF FAREHAM
 * [SEAL] A. C. GEDDES
 * R. L. BORDEN         [SEAL]
 * G. F. PEARCE         [SEAL]
 * JOHN W SALMOND       [SEAL]
 * ARTHUR JAMES BALFOUR [SEAL]
 * V S SRINIVASA SASTRI [SEAL]
 * A SARRAUT            [SEAL]
 * JUSSERAND            [SEAL]
 * CARLO SCHANZER       [SEAL]
 * [SEAL] V. ROLANDI RICCI
 * [SEAL] LUIGI ALBERTINI
 * [SEAL] T. KATO
 * [SEAL] K. SHIDEHARA
 * [SEAL] M. HANIHARA

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