Wall tolerance applies to ends only, end preparation per ansi b16.25
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: Threaded elbows and bends of iron or steel (other than cast iron or stainless steel) for pipes and tubes
NSN 5925-01-588-1762
NSN 5855-00-106-1640
NSN 5915-01-494-9550
NSN 6150-01-211-8062
NSN 6610-01-338-0628
NSN 7035-01-119-6271
NSN 5905-00-929-8838
NSN 5998-00-893-7047
NSN 6135-01-280-2883
NSN 6110-01-548-4762
NSN 5855-00-231-7790
NSN 5935-00-798-2306