1/4" NPT (1/4-18 NPT) vs 5/16" barb (gas) (5/16" hose barb): specs compared
Updated 05 September 2026.
5
specs differ
1/4" NPT (1/4-18 NPT) and 5/16" barb (gas) (5/16" hose barb) differ on 5 specs: designation, size / thread, fitting form, seals on, rating / role.
| Spec | 1/4" NPT (1/4-18 NPT) | 5/16" barb (gas) (5/16" hose barb) |
|---|---|---|
| Designation | 1/4-18 NPT | 5/16" hose barb |
| Size / thread | 1/4-18 NPT tapered | 5/16" (7.94 mm) barb tail |
| Fitting form | tapered, 60 degree | ribbed hose barb |
| Seals on | on the thread flanks with PTFE tape or paste | barb ridges plus a worm clamp on the hose |
| Rating / role | US pipe thread on some regulators, gauges and check valves | the standard gas-side barb on ball-lock and pin-lock disconnects |
Questions and answers
How do 1/4" NPT (1/4-18 NPT) and 5/16" barb (gas) (5/16" hose barb) compare?
1/4" NPT (1/4-18 NPT) and 5/16" barb (gas) (5/16" hose barb) differ on 5 specs: designation, size / thread, fitting form, seals on, rating / role.