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 6220-01-451-3056
NSN 5975-00-976-4262
NSN 5935-01-383-2911
NSN 6105-00-090-3243
NSN 5905-01-098-9156
NSN 5990-00-081-1266
NSN 5998-00-246-6895
NSN 6110-01-527-1155
NSN 6130-00-238-8447
NSN 5910-00-991-7178
NSN 4140-00-935-5360
NSN 5895-01-305-7395