Ordnance provision system. Ordnance catalog (ordnance provision system): [Group D], Gun, 155-mm, M1 and M1A1, and carriage, gun, 155-mm, M1, major items, maintenance parts and equipment required for maintenance of gun, 155-mm, M1 and M1A1, mechanism, recoil, gun. 155-mm, M3, carriage, gun, 155-mm, M1, and limber, carriage, heavy, M2, addendum; Jan. 1, 1943.