"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. Working Width in. 6 1/8, Height in. 5 1/2, Reflective Yes, Material Rubber, Rope Length ft. 3, Includes qty. 2, Length in. 18. 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"