R1-1/2 vs G1-1/4: specs compared
Updated 05 September 2026.
47.803 mm
R1-1/2 wins on major diameter
On major diameter, R1-1/2 leads: 47.803 mm versus 41.91 mm.
| Spec | R1-1/2 | G1-1/4 |
|---|---|---|
| Designation | R1-1/2 | G1-1/4 |
| Major diameter | 47.803 mm | 41.91 mm |
| Threads per inch / pitch | 11 | 11 |
| Thread form | tapered, 55 degree | parallel, 55 degree |
| Seals on | on the thread flanks with PTFE tape or paste | flat washer or bonded seal on the face |
Questions and answers
Which has the higher major diameter, R1-1/2 or G1-1/4?
On major diameter, R1-1/2 leads: 47.803 mm versus 41.91 mm.
How do R1-1/2 and G1-1/4 compare?
On major diameter, R1-1/2 leads: 47.803 mm versus 41.91 mm.