Features: natural rubber material, double bearing, quiet and environmental protection, thick flat plate, 360 degree free rotation, free start and stop, strong load, easy to install, strong wear Free combination of casters, can be freely matched according to your needs A: directional wheel x4 B: universal wheel x4 C: 2x directional wheel + 2x universal wheel Product Name: Heavy Duty Castors Colour: Black Specifications: 4 inches, 5 inches Type: directional wheel, universal wheel Material: rubber 4-inch single wheel load: 100KG 5-inch single wheel load: 110KG Suitable for: warehouses, shelves, trolleys, flatbeds, scaffolding, logistics and transportation, factory terminals, etc. note: 1. Package Content: Casters x4 2. The size of this product is measured by hand. There may be a slight error. Please refer to the actual product. 3. The products are taken in kind, due to lighting / light and other reasons may have a little color difference, please refer to the actual product. 4. We are 1-2 days delivery, 15-25 days to arrive, if you have any questions, please contact us, we strive to make you satisfied.