WATTS® Air Vent Valve, Automatic, Series: FV-4M1, 1.45 to 150 psi, 33 to 240 deg F, Top Vent Tapping, Brass, 2-15/16 in H
Body and cover are brass construction Air vent with silicone rubber seal Impurities do not usually affect function as maximum float line of water is always lower than the valve seal Float is high temperature resistant polyethylene Suitable for use with glycol systems Can be disassembled for inspection and cleaning