Don't let your prized possessions roll away with the BISupply Wheel Chocks and Tire Dock. Heavy-duty wheel chocks are designed to keep trucks, RVs, boat, horse, and travel trailers right where you left them. Made from a rigid plastic these wheel chocks are attached with a nylon rope handle for easy carry and removal. 8.5 x 4.8 x 4in (21.6 x 12.19 x 10.2cm) trailer chocks feature a ribbed surface and anti-slip EVA rubber foam pads to grip the ground and stabilize wheels up to 26in (66cm) in diameter. Chock dock fits trailer jack wheels sized 8-10in (20.3-25.4cm) and has a drainage hole to keep your caster wheels dry. A full 12in (30.5cm) diameter jack pad takes on the stress of the trailer weight and keeps your jack stand wheel from sinking into soft ground. Warning: This product can expose you to chemicals which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm.