MIL-STD-637A (NOTICE 2), MILITARY STANDARD: MACHINE AND AUTOMATIC GUNS AND MACHINE GUN TRAINERS THROUGH 30-MM (21 AUG 1989) [NO S/S DOCUMENT]., MIL-STD-637A dated 13 February 1961 and Notice 1 dated 10 December 1962 areInactive for new design and are no longer used by the Navy except forreplacement purposes. They may also be required for foreign military salesspares procurement.