Masks:For all Full Face masks: Masks that cover nose and mouth and reach to middle of lower lip, except:
Chin Full Face Masks:
Regular full face masks reach to the middle of lower lip but Chin Full Face masks reach below the chin, (reach below lower jaw / fit over the chin).
Gel Liner for Chin Full Face Masks are under "Chin Full Face Gel Liner"
Masks that do not have a forehead arm like Quattro FX and AirFit F10, as these masks have a common complaint that they often leak. Masks need to be connected at upper and lower boundaries and not at mid and lower boundaries, as a result they are notorious for leakage and the gel liner might still not seal completely, but it will still be fully protective from facial trauma.
Small and Large
Small Gel Liner covers Small and Medium Full Face Masks.
Large Gel Liner covers Large and X Large Full Face Masks.