The Hot Floors Silver Thermostat is compatible with all Hot Floors Underfloor Heating Systems, available as an upgrade with all the underfloor heating kits we supply. The silver thermostat is exactly the same as the standard white thermostat, just a different colour. The silver thermostat is also BEAB approved when used with the 160 Watt Underfloor Heating Mats, and VDE approved when used with the other systems.