As differentiated by quality control iaw mil-q-9858
A fluid line fitting having a pipe, tube or hose connection or a through hole to accommodate a bolt, fluid passage on one end. The other end must have an external or internal thread for connecting a mating part to form a self-sealing coupling assembly. The fitting has either a self-sealing feature for the purpose of automatically shutting off the flow of fluid when disconnected from its mating half, or, if it has no self-sealing feature, is specifically designed to mate with a fitting with a self-sealing feature. For self-sealing fittings with a quick disconnect end, see coupling half, quick disconnect. For fluid line fittings without a self-sealing feature, see coupling (as modified).
NSN 6135-01-316-9794
NSN 6130-00-859-2225
NSN 5895-01-541-8367
NSN 6320-00-115-0883
NSN 6650-00-466-1697
NSN 6685-01-398-9807
NSN 5998-01-426-8989
NSN 6220-01-007-6094
NSN 6105-01-522-4191
NSN 5960-01-351-5074
NSN 5925-01-539-0576
NSN 6110-01-026-1236