Breathable Cover made with a single layer 3D Polyester Spacer Fabric 6mm thick. 3D construction, which reduces heat build-up, allows consistent air circulation and provides high moisture transfer. Rather than 3 separate layers this is just one single layer. Prevents creasing which could break down your skin leading to medical problems. Comfortable cushioning and shock absorbency with excellent recovery properties: Extremely high air distribution in all directions: soft cushioning effect: Excellent recovery: High shock absorption: Very low weight: Colours available Black, Beige, Silver & Olive Green. All Covers now give you the option of Standard 6oz Nylon sides or 3mm Black Neoprene.