Watts 3/4 LF100XL-DP-TT-150 3/4-Inch Lead Free Temperature and Pressure Relief Valve Provides the least expensive and proven means for protection^3/4-Inch valve body length, 1-1/8-Inch long shank^Self-closing safety valve for hot water heaters^3/4-Inch MPT male pipe thread inlet and female outlet^150 psi maximum