A combination regulator; first stage reduces cylinder outlet pressure to 10 psi, and then second stage maintains a stable working pressure of 11“ water column. Overpressure Protection Device: Limits environmental propane release in case of regulator malfunction to a value less than 2 psi, significantly lower than that mandated by UL standard 144. Kit includes the plastic vent covers required by RVIA For use on RVs with single vertical tank or horizontal tank. Cavagna Group, Dual Stage Regulator Type 524AS, Horizontal Vent, Overpressure Protection Device, ZAMAK body.