Dimensions: 31-1/4" x 5" x 5-3/4" (fits frames 2" to 3" wide and up to 4" tall) High Performance: Boat trailer rails play a vital role in loading and unloading your boat, improving efficiency and the overall boating experience Premium Materials: Boat trailer rails are made of premium steel and rubber, with a durable galvanized finish for extended life How to Use: Boat roller guides attach to the trailer's transom (inside the pontoons) for width adjustment Installation and Package: Bolts onto the trailer's transom. Package includes 1 set of boat trailer rails, installation instructions, and hardware