Rigid industrial medium-heavy duty caster, 400 Series. Polypropylene wheels give easy mobility to heavy loads on smoothhard surfaces. The wheels are nonmarking, light in weight, and have high-impact strength. They resist water and chemical absorption. The body of the caster is made of welded 3/16" steel. Its versatility makes it ideal for most general medium-heavy duty industrial applications. Ideal for platform trucks, wire shelving, warehouse trucks, and carts.