Double Barrel “chain driven” Trailer Gate assist has a unique two spring design for extra power, is the shortest on the market and takes up the least amount of rail space. Is designed to operate on a 10″ to 15″ high trailer top rail. Reduces 134 lb. gate to less than 5 pounds allowing you to raise and lower your tailgate with just one finger. Includes mounting hardware. Dimensions: 54″L x 2″W x 4.5″H Note: Modifications may be needed when attaching to a trailer with round tube frame or rails.