JFATXTT Boat Trailer Ribbed Wobble Roller: 5in OD x 3in W, fits 7/8-9/8" shafts, ideal for standard trailers. Made of durable polyurethane, it resists wear, corrosion, and impact in marine and road conditions. Ribbed surface boosts grip, wobble design adapts to hulls, preventing scratches. Includes 8 gaskets and 4 cotter pins for secure, rattle-free installation. Easy to set up with no special tools; cleans with water for low-maintenance, reliable boat transport support.