Shepherd 4 In. Polypropylene Medium-Heavy Duty Rigid Caster is a rigid industrial caster designed for medium-heavy duty use, part of the 400 Series. Its polypropylene wheels easy mobility for heavy loads on smooth, hard surfaces, making it for various industrial applications. These wheels are nonmarking, lightweight, and possess high-impact strength, ensuring durability and long-lasting performance. They also resist water and chemical absorption, adding to their versatility. This caster is i for use on platform trucks, wire shelving, warehouse trucks, and carts, providing reliable support and smooth movement. Please note that fasteners are not included. Model Number: