3-1/2-6NH vs 3/4-14NPSH: specs compared

Updated 05 September 2026.

107.77 mm
3-1/2-6NH wins on major diameter

On major diameter, 3-1/2-6NH leads: 107.77 mm versus 26.29 mm.

Spec3-1/2-6NH3/4-14NPSH
Designation3-1/2-6NH3/4-14NPSH
Major diameter107.77 mm26.29 mm
Threads per inch / pitch614
Thread formstraight (parallel), 60 degreestraight (parallel), 60 degree
Seals onrubber gasket in the female swivelflat washer or gasket in the coupling

Questions and answers

Which has the higher major diameter, 3-1/2-6NH or 3/4-14NPSH?

On major diameter, 3-1/2-6NH leads: 107.77 mm versus 26.29 mm.

How do 3-1/2-6NH and 3/4-14NPSH compare?

On major diameter, 3-1/2-6NH leads: 107.77 mm versus 26.29 mm.

Compared here