2/3KW Heater with Thermostat Heater Diameter: 50mm Overall Length: 340mm Overall Height: 120mm Volts: 240vac Hz: 50/60 KW: 2.0/3.0 Sensor built in, the heater is controlled by a thermoregulator on the side of the module. Fittings: 1.5" white plastic female sockets to connect to plumbing Required flow rate: Set by the pressure switch, this switch will need to be pressurised, if it runs straight to a big bore out let with no bends, there will be no back pressure and it may not work. Pressure switch operated by an extra cord. High limit thermal cut out built in. This unit is rated IPX5 and has CE approval. Please note that all electrical spare parts must be fitted by a qualified electrician/Hot tub Engineer