Protect yourself from excessive temperatures and pressures in you water heater with AGA certified temperature and pressure relief valve. All valves have pressure settings factor set at 150 PSI. Corrosion resistant: all metal parts exposed to water are copper or stainless steel allows. The all brass valve body has no gaskets - no leaks - engineered simplicity of design. Probe epoxy coated to prevent corrosion buildup. 4" actuator for installation in hot outlet line.