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 5895-00-127-9533
NSN 5935-01-202-1452
NSN 6110-00-372-3620
NSN 5999-00-936-6032
NSN 6320-00-194-4252
NSN 6150-01-240-2320
NSN 6220-00-538-9514
NSN 5910-01-224-6529
NSN 2925-00-391-0331
NSN 5895-01-351-2998
NSN 6240-01-182-1895
NSN 5985-01-252-3665