Ibirdie Outdoor Waterproof And Weatherproof Hot Tub Cover 85 X 85 Inch Fit 84 X PROPER DIMENSIONS -The hot tub cover measures 85''L x 85''W x 20''H. NOTE: This cover can not be used by itself without an insulated hard cover under it. To ensure that the hot tub cover is suitable for your hot tub, please measure the length and width of the hot tub before ordering, and order a cover that is longer and wider than the hot tub. WEATHERPROOF - Perfect for protecting your hot tub and hard top cover from inclement weather, our hot tub covers protect against falling debris, rain, snow, hot sun, and more, keeping your hot tub safe and in good condition. WELL MADE - iBirdie Hot Tub cover is made of heavy-duty fabric with a waterproof coating. All seams are double-stitched for strength and have a sealant attached to the seams to prevent tears, leaks, etc. AIR VENTS DESIGN - Both sides are designed with air vents to expel moisture from the interior. Also designed with two fabric handles, it is easy to put on and take off. Please note: This hot tub cover can not be insulated; you still need to use the hard insulation cover. SECURE FIT - Four adjustablebuckles and waterproof zippers on each corner ensure a secure fit for your spa cover, even in strong winds.You can trust our cover to stay in place and keep your spa protected, no matter the weather.