Genie Universal Garage Door Extension Springs with Safety Cables, Black with Dark Blue End , Appx. 25-inch By 140-pound 90# spring Fits doors 8' x 7' and 9' x 7' 1 Spring for box, but 2 springs to complete operation larger doors need larger springs 120 & 130# springs fit 9 x 7' and 8' x 7' and 16' x 7' 140# Springs fit 16' x 7' doors