4.0A. Warm Tiles electric floor warming cables deliver affordable comfort and luxury. Easily installed on subfloor or concrete slab, in thin-set or self-leveling compound materials. Use under ceramic, slate, stone, engineered wood, or laminate floor coverings. Designed to supply at least 12W (watt) per sq ft (square foot) when installed properly. 120V (volt). UL listed (Underwriters' Laboratories) to USA and Canadian Safety Standards. This kit covers up to 42 sq ft for a floor above a heated space or basement. Above an unheated space or on slab construction, the kit covers up to 33 sq ft. SKU 274453 (non-programmable thermostat Model No. GT1) and SKU 274461 (programmable thermostat Model No. GTS1) stocked/sold separately.