ANSI B1.20.1 - NPT - American National Standard Taper Pipe Threads
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WebNPT threads may be referred to as MPT ('Male Pipe Thread'), MNPT, or NPT (M) for male (external) threads, and FPT ('Female Pipe Thread'), FNPT, or NPT (F) for female (internal) threads. Note that FPT and MPT are not authorized designations per the ANSI standard. Characteristics of NPT (also known as ANSI/ASME B1.20.1 Pipe Threads, General Purpose):
DA: 84 PA: 66 MOZ Rank: 96