This 12 volt flexible impeller pump is specifically manufactured for wakeboard and ski boats for water ballast transfer. This quick and convenient kit will custom shape the boats wake to suit any boarder's style. The pump is capable of transferring approx 38KG (38 litres) of water ballast per minute filling or emptying a 200 litre ballast tank in just over 5 minutes. The pump is reversible to both fill and empty ballast tanks in quick time, simply and easily. Self priming, won't airlock and has exclusive run dry protection and ignition protected motor. Supplied with a special yellow polyurethane impeller that handles reversing with ease. Supplied with high quality dash mount switch unit marked "Ballast" fill and empty, complete with fitted connectors and long heavy duty electrical wiring. Pump size : 181mm length x 121mm wide x 92mm high Hose connection ports - dual 1/2" internal female thread and 25mm external hose barb.