"This 2-pack of heavy-duty Ironton Aircraft Wheel Chocks is designed for use chocking the wheels of aircraft or ground equipment, or for anchoring large pipe. Tough ribbed rubber construction. Material Rubber, Rope Length ft. 3, Length in. 18, Reflective Yes, Working Width in. 6 1/8, Height in. 5 1/2, Includes qty. 2. Reflective tape on 3 sides for high visibility 3 ft. nylon rope connects the pair of chocks to provide easy, safer removal 18 in. L x 6.1 in. W x 5.5 in. H large size chocks"