High Quality Material: The Boat Trailer Roller is made of high quality plastic processing, which is sturdy and durable for long term use. WIDE APPLICATIONS: Trailer Keel Roller is a universal accessory, widely used in boats, yachts, trailers, yacht motorcycles and more, which can fully meet your needs. Function: The Marine Keel Roller can help you load the boat on the trailer without scratching your car, helping you improve work efficiency, and it is very practical at the same time. Easy to Use: The Boat Trailer Wobble Rollers are exquisite in workmanship, not easy to break, high temperature resistant, easy to use and install, saving your energy and time. Ideal Parts: Marine Wobble Roller has high reliability and stable performance, and can directly replace old or damaged parts. Size Chart: 12cmx7.5cmx1.98cm/4.72inchx2.95inchx0.78inch Package Includes: 1 Trailer Keel Roller(2 Pack) Note: Please allow slightly errors due to manual measurement and different monitors.