There are three sizes available to fit most round hot tubs on the market. Please check the detailed dimensions in the pictures and product information. We recommend measuring your hot tub to choose the proper size. The outdoor round hot tub cover is made of 210D oxford fabric with an inner silver coating. This durable jacuzzi cover is waterproof, snowproof, dustproof, and lightweight, keeping your outdoor round hot tub dry and clean. The spa cover features a drawstring design on the bottom with cord locks to keep it secure on windy days. The round hot tub cover goes completely over the whole tub, covering the heating element and motor to prevent heat from escaping and help maintain water temperature. It is easy to clean by hosing it down with water and letting it dry in the sun. A storage bag is included for easy storage. Package includes one hot tub cover and one storage bag. The hot tub is not included.