R600 Series second-stage regulators are UL listed designed to reduce the outlet pressure from a first-stage regulator in domestic installations. Type R622 is designed for Two-Stage domestic applications up to 1 400 000 BTU per hour / 15,8 SCMH. Type R622 contains a high performance relief valve and a large 3/4-inch screened vent to limit downstream pressure to less than 2 psig / 0,14 bar in an overpressure situation. Types R642 and R652 are designed in an angle body and back mounted design.