2-1/2-8NPSH vs 2-1/2-8 NPT: specs compared

Updated 05 September 2026.

73.02 mm
2-1/2-8 NPT wins on major diameter

On major diameter, 2-1/2-8 NPT leads: 73.02 mm versus 72.16 mm.

Spec2-1/2-8NPSH2-1/2-8 NPT
Designation2-1/2-8NPSH2-1/2-8 NPT
Major diameter72.16 mm73.02 mm
Threads per inch / pitch88
Thread formstraight (parallel), 60 degreetapered, 60 degree
Seals ongasket in the couplingon the thread flanks with PTFE tape

Questions and answers

Which has the higher major diameter, 2-1/2-8NPSH or 2-1/2-8 NPT?

On major diameter, 2-1/2-8 NPT leads: 73.02 mm versus 72.16 mm.

How do 2-1/2-8NPSH and 2-1/2-8 NPT compare?

On major diameter, 2-1/2-8 NPT leads: 73.02 mm versus 72.16 mm.

Compared here

2-1/2" NPSH straight hose thread (2-1/2-8NPSH)2-1/2" NPT (National Pipe Taper) (2-1/2-8 NPT)