Rule-Mate 1500 GPH 12 Volt Fully Automated Bilge Pump The Rule-Mate® 1500 GPH pump consists of a powerful Rule® bilge pump and a highly intelligent circuit board in a single housing. 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 Warning [https://productimageserver.com/prop65/6pt.png]WARNING: This product can expose you to chemicals including FORMALDEHYDE (GAS) which is known to the State of California to cause cancer. For more information go to P65Warnings.ca.gov [http://P65Warnings.ca.gov].