Wireless key for EasyControl ensures reliable wireless communication between the controller and the heater. With the key acting as a wireless receiver between the control and the boiler, the EasyControl becomes a smart internet-connected room thermostat that offers customers a simple and stylish solution to managing their heating. Compatible with the Worcester Bosch EasyControl smart thermostat. Suitable for Combi & System Boilers Fits Custom Backplate Rechargeable Battery-Operated No Key Override LED Indicator Internet Connection Required Suitable for Combi & System Boilers Fits Custom Backplate Rechargeable Battery-Operated No Key Override LED Indicator Internet Connection Required