The unique design of the Studor Tec-Vent provides plumbing ventilation to prevent the loss of water seal in traps without the need for costly roof penetration and vent piping. Used as the primary source of venting for branch fixtures in large buildings, the valve offers excellent protection for the trap water seal. The valve is classified in accordance with UL 2043. When part of an Engineered System, it can be installed in return and supply air plenums. The valve has a flame-retardant rating and UV-resistant properties.