Protect your spa cover and further insulate your hot tubs water with the spa cover protective thermal insulating blanket. Place the thermal blanket on the surface of your tubs water before putting on your spa cover, the blanket will protect your cover from moisture, chemical vapors and heat while helping your hot tub maintain a more consistent temperature without using more energy. You can find this useful hot tub accessory at a great price with great service and quick shipping at HotTubWorks.com. Product sizes available: 7 ft. x 7 ft.; 8 ft. x 8 ft. Blanket thickness: 15 mil Protects vulnerable areas like seams and hinges on your spa cover from heat, moisture and chemical vapors Thermal blanket is lightweight and easy to put on and take off Blanket is easy to trim to fit your hot tub perfectly Helps hold in water heat while protecting your cover to save you money and energy Please note: All blankets will have a seam in the middle