The SwithcH2O has 3 probes, in 304 stainless steel, are set in an epoxy-resin filled holder and they represent on, off and common. “On” must be cut to a position 50mm to 15mm, from the base of the pump and the “off” cut to a position from 40mm to 5mm from the base of the pump. In any application these two probes must have a minimum difference of 10mm. “Common” must always be below the level of the “off” probe. It is supplied with 10 metres of low voltage, PVC power cable. Instruction how to fit control panel to Puddle sucker pump with SwitH2O are in "How to" page under Help and Advice.