USA Design: Can be used with electric drill Specially Tailored for Travel Trailers: Rvdeaa researched all mainstream the market and developed the perfect matching Wheel Stabilizer X CHOCK Extended; Wheel stabilizer for Travel Trailers, Class A Moto home, Fifth wheel trailer, Travel Trailer, Toy Hauler etc Ultra-fast: After long-term research and development, the fourth-generation camper wheel block has been upgraded, which can be used with an drill; This is the fastest wheel stabilizer to open to date Firm and Stable: Rvdeaa X CHOCKS EXTENDED is made of world-class high-quality steel, thickened and heavier, double the thickness of goods on the market, anti-corrosion, suitable for outdoor use Independent Research and Development Center: Rvdeaa provides perfect stability by utilizing the reaction force to the tire through the exclusive design center point of X chocks wheel stabilizer; Increase the safety of the car Fitment and 5-star Service: Rvdeaa X WHEEL CHOCK EXTENDED extend to fit wheel distances from 4' to 17' on travel trailers; And provides 5-star service, please feel free to contact if you have any questions. Immediately solve it for you.