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 5998-01-412-4977
NSN 5945-01-152-2780
NSN 6110-00-647-3932
NSN 5998-01-427-3776
NSN 6150-01-258-3171
NSN 4140-01-379-8796
NSN 6145-01-204-5540
NSN 5910-01-274-9065
NSN 5905-00-492-1032
NSN 6130-01-018-2976
NSN 5965-00-280-9677
NSN 6685-01-330-4910