G2-1/2 vs R3: specs compared

Updated 05 September 2026.

87.884 mm
R3 wins on major diameter

On major diameter, R3 leads: 87.884 mm versus 75.184 mm.

SpecG2-1/2R3
DesignationG2-1/2R3
Major diameter75.184 mm87.884 mm
Threads per inch / pitch1111
Thread formparallel, 55 degreetapered, 55 degree
Seals onflat washer or bonded seal on the faceon the thread flanks with PTFE tape or paste

Questions and answers

Which has the higher major diameter, G2-1/2 or R3?

On major diameter, R3 leads: 87.884 mm versus 75.184 mm.

How do G2-1/2 and R3 compare?

On major diameter, R3 leads: 87.884 mm versus 75.184 mm.

Compared here