The EPH Single Channel Zone Central Heating Programmer Timeswitch - A17 is a programmable thermostat suitable for central heating boilers. It features a 7-day, 5/2 day, or 24-hour programmable schedule with 3 periods per day. The thermostat is wall-mounted, powered by 230V corded electric, and has a rectangular shape with push-button controls. Other notable features include a boost function, compatibility with various brands and models, and a 2-year manufacturer's warranty. This white plastic thermostat is designed for line voltage systems and has a system switching capacity of 3(1)A 230Vac.