Peerless 0155305 Auto-Trac Tire Traction Chain - Set of 2 Worry-free self-tightening ratchets provide automatic tightening and centering Easy installation and removal in minutes Do not exceed 30 MPH with these chains on Diamond pattern cross chain provides a smoother ride and superior traction Meet class 'S' clearance requirements Worry-free self-tightening ratchets provide automatic tightening and centering Easy installation and removal in minutes Eliminates loose chains and retightening stops Diamond pattern cross chain provides a smoother ride and superior traction Meet class 'S' clearance requirements