Ordnance provision system. [Ordnance catalog (ordnance provision system): [Group C], Howitzer and carriage, 75 mm, M2, M3 and M3A1, major items, maintenance parts and equipment required for maintenance of howitzer, pack, 75 mm, M1A1 and carriage, howitzer, 75 mm, M3A1, addendum, Changes 3; July 10, 1942.