4" BSP-005PF, 1/2HP, 2-Wire, 115V Single-Phase, 60Hz with a 1" FNPT discharge is an automatic bottom suction submersible pump designed for cistern applications. Also can be used as an irrigation pump operating on/off from a hand held nozzle or solenoid valve. It includes both a built in pressure and flow switch. The pump will turn on when the discharge pressure drops below 45 psi and the pump will shut off when the flow stops completely. The pump has a built-in flow-inducer ensuring motor longevity even in low water/high heat environments. Has an internal built-in check valve. Thermally protected simply reset power to the pump when thermal overload has tripped. 12 Month Replacement Warranty ... *** Pricing includes a FREE Cistren Float Intake.