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 5895-00-477-7823
NSN 5965-00-045-7156
NSN 6135-01-372-5191
NSN 5965-01-512-9525
NSN 6620-01-345-4835
NSN 5935-00-656-7253
NSN 5990-01-109-5295
NSN 6150-00-894-1984
NSN 6240-00-737-2775
NSN 5930-01-028-2226
NSN 5935-01-647-1571
NSN 6650-01-556-9696