Wreckmaster™ black skates set of 4. Wreckmaster™ skates (Slippery Jims) dramatically reduce friction during the loading and unloading of vehicles with damaged or stuck wheels. The skates wedge between the wheels and the ground, minimizing friction. This translates to less stress on your winch, wire rope and other components. With skates in place, the disabled vehicle will slide easily into the loaded or unloaded position. The skates have an interlocking tooth system, and individual skates may be joined together to form larger skates for wide tires. Each skate also has a notch to accommodate vehicles without wheels. Wreckmaster™ skates are constructed of a super tough polymer for greater durability. Instructions included.