This 8" 4 Pack Plate Caster is made of thermoplastic rubber and steel and can carry a maximum load of 2400 pounds. The pack includes 2 swivel and 2 rigid caster wheels, with swivel casters capable of rotating 360 degrees. The caster wheels have a 2-inch wheel width and 8-inch wheel diameter, with a top plate measuring 4" x 4-1/2". They are versatile, easy to clean, and suitable for a range of applications. The product also comes with a 90-day return policy and a 100% satisfaction guarantee.