Composition: These wheels typically consist of a polyurethane tread bonded to a core, which is often made of cast iron or steel for high load capacity.Design: They feature a standard cylindrical profile with a central bore containing double ball bearings (often 6204 series) to ensure smooth, low-friction rotation under heavy weight.Performance Characteristics:Floor Protection: The red polyurethane material is non-marking, silent, and shock-absorbing, making it ideal for use on epoxy or painted warehouse floors.Durability: They offer high resistance to wear, chemicals, and abrasion.Load Capacity: Depending on the specific dimensions (common sizes include 80x70mm or 80x100mm), a single wheel can often support between 450kg to 850kg.