D-shaped industrial quality rubber dock bumper. Designed for truck trailer bumpers building columns walls dock levelers and loading docks. Compresses on impact to reduce damage to structures and vehicles. Includes (3) 5/8in Mounting holes with 1-3/8inD countersink and a 2.25inD full length through-hole. Made from industrial rubber construction resistant to moisture oil and temperature variation. Measures 35.5inL x 4inW x 4inH overall.