The Onspot Automatic Tire Chain kit helps operators of Autocar's Xspotter yard tractor quickly engage or disengage chains when dealing with snow- or ice-covered yards. With Onspot, the operator flips a switch to start the process while the vehicle is moving forward or in reverse. The chains are mounted to the vehicle's suspension system and, using centrifugal force, rotate at the same speed as the wheels. When not needed, they retract to avoid coming into contact with the pavement.