Locking casters: double locking and double for maximum safety. Our casters are fitted with brakes for further safety and stability and feature a double lock mechanism for swivel and wheel swivel.Swivel Casters: Dual for easy 360-degree swivel and easy assembly with brakes. Wheels can smoothly transport heavy loads from one place to another.Premium Material: Our casters are made of industrial-grade electrophoresis brackets, precision , and durable polyurethane wheels for and protection from corrosion and rust. The PU wheel does not hurt the ground, moves flexibly, and leaves no trace on the floor.Double Locking and Double : Double locking and double are provided to make the product more stable and reliable, with its excellent maneuverability, double locking and double ball bearing design, the swivel wheels allow you to move easily and precisely through narrow corner.Widely used and easy to assemble: It is easy to assemble and has a built-in stopper for safety. With its innovative design, the caster is a must-have for any home. Casters and wheels for carts, furniture, wire shelves, storage racks, workbenches, tool boxes, wheelbarrows and more.Product Name: Universal WheelSize: 12 x 9.6 x 3.5cmColour: BlackMaterial: PolyurethanePackage Contents:4 x Universal wheelsOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.