DUO QD Gas8 vs FFL: specs compared
Updated 05 September 2026.
5
specs differ
DUO QD Gas8 and FFL differ on 5 specs: designation, size / thread, fitting form, seals on, rating / role.
| Spec | DUO QD Gas8 | FFL |
|---|---|---|
| Designation | grey QD, 8mm push-in tail | 1/4" FFL (7/16"-20 UNF) |
| Size / thread | snaps over the gas post; integrated 8mm push-in tail | 7/16"-20 UNF female thread, 45 degree flare seat |
| Fitting form | snap-on gas QD with integrated push-in | SAE 45 degree flare, female |
| Seals on | O-ring over the post shoulder; 8mm push-in O-rings on the tube | mates against a male 45 degree flare face |
| Rating / role | the gas-side ball-lock disconnect with a built-in 8mm Duotight, no separate flare fitting needed | the female half of the homebrew flare standard |
Questions and answers
How do DUO QD Gas8 and FFL compare?
DUO QD Gas8 and FFL differ on 5 specs: designation, size / thread, fitting form, seals on, rating / role.