The Invincible Marine BR59202 Trailer Jack Wheel Stop prevents loose and shifting trailers, and protects your driveway from dents and chipped concrete. This wheel stop is made from 100-Percent high-density polyethylene and is UV protected for long-lasting strength. This 6-1/4-inch wheel stop is used with boats, personal watercrafts and other floatation devices. A circular disc, place your trailer"s tire onto the Jack Wheel stop and know your trailer is secure and stationary. Whether you"re outfitting your boat for the first time, or replacing well-worn nautical parts, this product is an essential accessory for your boating and domestic needs, and is perfect for nautical journeys and mechanical maintenance. Precision and reliability are the marks of quality that this product has proven time and time again, guaranteeing steadfast performance with each use. The Invincible Marine BR59202 Trailer Jack Wheel Stop comes with a 1-year limited warranty and protects against manufacturing and workmanship defects. Rugged, tough and reliable, Invincible Marine is well-known for their hardworking nautical line. for freshwater and saltwater boating, Invincible Marine designs products for avid fishermen and weekend boaters. Quality, utility and innovation go into every Invincible Marine product giving you more time on the water.