Special o-ring material, per mil-p-5510c, do not dupe to any other nsn
An adapter having machine threads (straight threads other than pipe or hose series) designed to accommodate a tube on one end or an unthreaded end designed to accommodate a tube. The other end has external or internal machine threads (straight threads other than pipe or hose series) and is designed to facilitate a gasket, preformed packing, washer, or the like to form a seal at the boss. It is designed to join a tube or tube fitting to a boss or boss fitting in a straight line on items such as tanks, housings, valve fittings, and the like. See also coupling, tube and nipple, tube.
Classification: Other fittings nesoi of iron or nonalloy steel
NSN 4140-01-142-8340
NSN 7035-01-010-8309
NSN 5910-01-082-2570
NSN 6130-01-570-7428
NSN 5975-00-763-5437
NSN 6320-01-380-0561
NSN 6620-00-703-0860
NSN 5998-01-062-0390
NSN 6685-00-231-8646
NSN 6240-01-079-8645
NSN 5945-01-348-4206
NSN 6685-01-543-6410