The size is 0.312 inches -26
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.
NSN 5990-01-386-5561
NSN 5920-01-541-5030
NSN 5905-01-398-2240
NSN 5985-00-826-1735
NSN 5895-01-228-5874
NSN 6110-01-381-7014
NSN 2925-01-302-7185
NSN 5985-01-555-2923
NSN 6645-01-575-6955
NSN 6645-00-359-5463
NSN 6220-01-131-5295
NSN 5985-01-414-2621