The National Pipe Straight Mechnical (NPSM) female fitting has a straight thread and an inverted 30° seat. The male fitting has a straight thread and a 30° internal chamfer. The seal takes place by compression of the seat on the chamfer. The threads hold the connection mechanically. A properly chamfered NPTF male will also seal with the NPSM female.
Standard:SAE,DIN,JIS,BS,ISO.
Material: Carbon steel, Stainless steel,Brass.