What is an NPSM screw?
ANSI is a combination of external thread , internal thread and parallel threads with a relatively precise fit in the machine coupling.
The accuracy is similar to G A class, but there is a gap of 0.03 or more, and it is Unified 2A and 2B grade.
The accuracy is similar to G A class, but there is a gap of 0.03 or more, and it is Unified 2A and 2B grade.
(ANSI) ANSI B1.20.1