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 6110-00-144-6763
NSN 6135-00-182-7008
NSN 5855-00-560-0110
NSN 5935-01-578-2356
NSN 5975-00-467-3999
NSN 5855-01-340-6541
NSN 5925-00-957-0884
NSN 7035-01-158-7673
NSN 6110-00-807-2501
NSN 6105-01-589-5907
NSN 6110-00-071-2783
NSN 5910-01-431-8109