This set of 4 heavy-duty plate casters is made of steel and features swivel casters with 2-inch phenolic wheels, providing a total load capacity of 6000 pounds. The casters have an 8-inch diameter and a top plate mounting style with a plate size of 4"x4-1/2" and mounting over heights of 9-1/2". They also have roller bearings with a hardened raceway for extra strength, quieter operation, and superior floor protection. The casters are easy to clean and install, making them an ideal choice for a range of applications.