The Rule 800 submersible bilge pump is ideal for small to medium craft , this new design has a vented body which helps protect against air locks and the thread port with check valve can stop back flow while also making it easy to install or remove for cleaningAdd a Rule-A-Matic Float Switch or Superswitch to make it an automatic bilge pump Features Light, compact pump for ski-boats and small to medium vessels. Tough plastic body. Quick release inlet strainer allows rapid cleaning. Low amp draw conserves batteries. Built-in Thermal Cut-Off. Check Valve included for Back Flow Prevention. Vented body to prevent air locking. Threaded port for easier installation and maintenance. For automatic operation use Rule Float Switches Specifications Voltage: 12 volt Connections: For 19mm (3/4") bore hose. Dimensions: 111mm high, 64mm x 74mm. Current Draw: 3.4(amps) Fuse Size: 5(amp) Output: Up to 50 litres/minute (11 gallons/minute) without check valve. Head: Max. recommended discharge head 2m.