THIS LISTING IS FOR (2) UNITS, A PAIR OF RISERS. 30,000 lbs. capacity per pair , Height: 10" , Overall Length: 66" , Level Length: 36" , Width: 18" - Elevate semi-trailers to loading docks for maximum serviceability during loading and unloading operations. Manufactured from heavy-duty aluminum treadplate for positive traction. Welded all aluminum construction. Wheel Risers are designed to facilitate compliance with OSHA requirements for a 10% maximum grade of ascending or descending loaded fork trucks.