The ESI ESRTP4RFW Programmable Room Thermostat in White is a wireless, wall-mounted device that operates on battery power (AA batteries included). It is specifically designed for central heating radiators and offers 4 heat stages with programmability for up to 6 periods per day. The thermostat features temperature sensor technology, analog/mechanical control style, and a display size of 1.57 inches. It is Amazon Alexa compatible and comes with a 3-year manufacturer warranty, making it a reliable and efficient choice for controlling the temperature in your home.