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 5945-00-244-1579
NSN 5960-01-365-5729
NSN 6610-01-180-7558
NSN 7035-01-194-9482
NSN 2925-01-625-6841
NSN 5965-00-907-5183
NSN 5965-01-435-1894
NSN 6130-01-004-6505
NSN 6130-01-483-8774
NSN 5935-01-158-5585
NSN 7035-00-205-8767
NSN 6130-00-308-2768