The Lay‑Z‑Spa EnergySense Thermal Hot Tub Cover works to keep your spa warm and make your hot tub up to 40% more energy efficient. This insulating cover offers a double layer of thermal insulation, improving heat retention and allows the water in your spa to heat up much faster. The thick internal layer of insulating cotton and anti‑mildew treated interior help to reduce heat loss even further, meaning you can save on running costs. Cover is made from ultra‑strong 3‑ply UV resistant and fully water repellent Duraplus™ material with double stitched seams, which provide additional strength and durability. Features safety lock clips on an adjustable strap for a tightly secured fit that won’t budge, even in windy conditions.