This automatic vent valve, 1/4 inch, is used in commercial, residential, and industrial hydronic heating applications to provide automatic or manual air venting in baseboards, radiators, convectors, and high points in piping systems. It consists of a 2-piece, chrome plated brass body construction, stainless steel check valve, copper thermostat assembly, brass disc bearing cover, neoprene O-ring, cellulose fiber disc, replaceable cartridge, and ABS heat-resistant handwheel. The cartridge can be easily maintained or replaced without system shutdown. This valve is ideal for use with hot water and low pressure steam systems. The maximum pressure is 125 PSI (8.6 BAR).