Suitable for hard and aggressive water conditions. For use with copper and stainless steel cylinders. Includes dual safety thermostat and fibre washer. Integral safety cut-out to prevent overheating. Pre-wired. Earthing post and cable clamp pre-assembled. Manual reset. This immersion heater element is ideal for use with the . Tesla 3k W immersion heater fitted with a dual safety protection thermostat rated at 15 amp. The unit is fully approved and tested to EN60335-2-73. The thermostat is also independently approved by BEAB to EN60730-1.