Rule Mate GPH Fully Automated Bilge Pump - 12V. The pump activated when the water reaches 2-1/2" and automatically shuts off when the pump senses no water against the impeller reducing the remaining water to approximately 5/8". Rule-Mate Intelligence Rule-Mate Bilge pumps have built-in programming that can sense when the pump is running but not pumping water. This is a very unique feature to bilge pumps because it protects the pump and the vessel especially the vessels batteries. If debris fouls the sensor or the pump becomes air-bound the pump will stop running and begin to "check" for water every 2-1/2 minutes. Once the debris is removed the pump will revert to its normal operation turning on when the water reaches 2-1/2" and shutting off at 5/8". 1500 GPH (6819 LPH) at 0' (13.6V) All-in-one pump and switch Extra long life heavy duty motor 1" NPS discharge with 1" AND 1 1/8" screw-on ports Three year warranty Specifications for Rule-Mate 1500 GPH Fully Automated Bilge Pump: Manufacturer: Rule Color: Black Voltage: 12 volts Features of Rule Rule-Mate 1500 GPH Fully Automated Bilge Pump Volts: 12V Operation: Automatic Gallons Per Minute: 25 Gallons Per Hour: 1500 Package Contents: Rule-Mate 1500 GPH Fully Automated Bilge Pump Rule RM1500A: Mate 1500 GPH Fully Automated Bilge Pump - 12V