R1-1/4 vs R1/2: specs compared
Updated 05 September 2026.
41.91 mm
R1-1/4 wins on major diameter
On major diameter, R1-1/4 leads: 41.91 mm versus 20.955 mm.
| Spec | R1-1/4 | R1/2 |
|---|---|---|
| Designation | R1-1/4 | R1/2 |
| Major diameter | 41.91 mm | 20.955 mm |
| Threads per inch / pitch | 11 | 14 |
| Thread form | tapered, 55 degree | tapered, 55 degree |
| Seals on | on the thread flanks with PTFE tape or paste | on the thread flanks with PTFE tape or paste |
Questions and answers
Which has the higher major diameter, R1-1/4 or R1/2?
On major diameter, R1-1/4 leads: 41.91 mm versus 20.955 mm.
How do R1-1/4 and R1/2 compare?
On major diameter, R1-1/4 leads: 41.91 mm versus 20.955 mm.