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 6135-01-359-5798
NSN 5895-00-515-6368
NSN 6240-00-477-3027
NSN 5910-00-928-3235
NSN 6620-00-905-6590
NSN 6620-01-381-6225
NSN 6650-01-437-0855
NSN 5965-01-225-6080
NSN 6220-01-189-7990
NSN 5835-01-023-8733
NSN 6620-01-501-7999
NSN 6130-00-066-9600