FITS ALL BRANDS OF HOT TUBS UP TO 73 INCHES This easy-to-fit Thermal Hot Tub Cover improves heat retention due to the thermal insulation making it up to 50% more energy efficient – saving you money! The cover is waterproof to HH 118 inches (3000 mm), as well as UPF 50+ providing protection from extreme weather conditions. The CleverSpa Universal Thermal Cover – Large Square, fits all square Hot Tubs up to 73 Inches, with and without an external motor. The removable zip-off door accommodates hot tubs with external motors. The webbing straps and locking clips provide a safe and secure fit. With improved energy efficiency, using your hot tub all year round couldn’t be easier, and the thermal cover makes this more viable. *We recommend using the CleverSpa Inflatable Cover Support to stop rainwater pooling and increase Hot Tub temperature retention further.