SuperSub Smart650 Bilge Pump. The unique design, high flow rate, and innovative technology place this pump in a class of it's own. The Whale SuperSub Smar650 measures 2 1/8" high by 2 15/16" wide, produces a flow rate of 650 gallons per hour, and utilizes Whale's Patented Electric Field Sensor Technology. Whale's Electric Field Sensor Technology senses the water level and automatically controls the pump, making it fully automatic. The unique dimensions make SuperSub Smart 650 the lowest profile automatic bilge pump on the market and the high 650 GPH flow rate on such a compact pump is almost unheard of. This pump is able to go where others cannot ensuring that the pump can access water deep down in the bilge of the boat or difficult to reach areas under engines or in personal watercraft.