The original pontoon rail fender clip Designed to fit both 1.25" and 1” square tube rails on pontoon boats Clamps securely to square tubing yet can be repositioned quickly and easily Constructed from durable ABS plastic. For lines up to 3/8 inch Allows for simple height adjustment of fenders Size:one size Designed specifically for the 1" square tube rails of Pontoon Boats. The mounting structure clamps securely to square tubing yet can be repositioned quickly and easily. Constructed from durable ABS plastic this fender adjuster allows for simple height adjustment for lines up to 3/8".