Standard pattern, Marine Ordnance ensign. A Blue Ensign with arms of Ordnance Office in the fly: 'azure, three field pieces on their carriages in pale or, in a chief argent as many cannon balls sable'. The shield has a gold border. The ensign is made of machine-sewn, synthetic bunting, with a linen hoist and a rope and toggle for hoisting. On the hoist: '12 x 6 H8/8345 - 99 - 125 - 0541 [broad arrow] 1972', on a label 'STANDARD PATTERN 26351 8345 - 99 - 125 - 0541 Flag. Marine Ordnance Ensign 12' X 6' approved by R. Hedger, date of sealing 21.2.80'.

The Ordnance Board ensign goes back to 1694 when ships employed by the civil branches of government were given Red Ensigns with the badge of the department in the fly. The Board of Ordnance was abolished in 1855 and a War Department fleet established with the same ensign. The Red Ensigns of government departments were changed to blue in 1864 in a general re-organization of state flags. From 1864 to 1890 the shield had a red border. In 1888 The Army Service Corps took over the War Office fleet. The cannon were reversed and the background colour changed to light blue in 1945. The flag was last in use at the MOD Proof and Experimental Establishment at Eskmeals, Cumbria.