6-8 NPT vs M24 x 1 female / 55/64-27: specs compared
Updated 05 September 2026.
168.27 mm
6-8 NPT wins on major diameter
On major diameter, 6-8 NPT leads: 168.27 mm versus 24 mm.
| Spec | 6-8 NPT | M24 x 1 female / 55/64-27 |
|---|---|---|
| Designation | 6-8 NPT | M24 x 1 female / 55/64-27 |
| Major diameter | 168.27 mm | 24.0 mm |
| Threads per inch / pitch | 8 | 27 |
| Thread form | tapered, 60 degree | fine parallel |
| Seals on | on the thread flanks with PTFE tape | washer inside the aerator housing |
Questions and answers
Which has the higher major diameter, 6-8 NPT or M24 x 1 female / 55/64-27?
On major diameter, 6-8 NPT leads: 168.27 mm versus 24 mm.
How do 6-8 NPT and M24 x 1 female / 55/64-27 compare?
On major diameter, 6-8 NPT leads: 168.27 mm versus 24 mm.