The Groth Model 12F-TWW-0 Pressure/Vaccum Relief Valve with Pipe-Away design was created to exceed industry needs. Extensive research and development have produced a product that achieves both superior sealing performance and industry leading flow rates, while also allowing customers to reach their required flow rates with a potentially smaller sized valve and utilize 10% overpressure technology. The pressure vacuum relief valve is designed to protect your tank from damage created by overpressure or excessive vacuum. Costly product evaporative losses due to normal tank “breathing” are greatly reduced. The Model 12F-TWW-0 are superior sealing valves developed to minimize fugitive emissions while providing increased protection and safety to tank equipment and on-site personnel.