The size is and for plumbing and heating
A fitting that forms an angle of less than 180 degrees (3.141 radians) from a straight flow. Both connecting ends have machine threads (straight threads other than pipe or hose series) designed to accommodate a tube or is unthreaded and designed to accommodate a tube. It may have side or heel inlet(s). See also elbow, pipe and connector, multiple, fluid pressure line.
Classification: Copper alloy tube or pipe fittings
NSN 6135-01-260-7180
NSN 5950-00-432-0915
NSN 6320-00-809-5744
NSN 6650-00-707-1417
NSN 6130-01-032-4958
NSN 5985-00-595-5392
NSN 6685-01-437-6292
NSN 5835-01-104-5707
NSN 5998-01-495-0882
NSN 5910-01-165-8646
NSN 6320-01-102-0799
NSN 6150-01-422-5903