Drain plug with o-ring for Sta-Rite Max-E-Glas, Dura-Glas, Max-E-Glas II, Dura-Glas II, Max-E-Pro, Dyna-Glas, Dyna-Max, Dyna-Pro, Dyna-Wave, Dyna-Jet, Dynamo, JWP pumps. Also fits MasterTemp, Max-E-Therm, and ETi heaters, Triton II filters, and Sta-Rite side-mount multiport valves.