These leveling rollers are made of sturdy metal, are wear-resistant, and have a long service life. You can move heavy objects easily and keep them in one place by adjusting the manual knob.It's great for high-performance furniture, workbenches, welding tables, vending machines, medical equipment, and laboratory equipment.Specification:Material: nylon + steel4 × leveling rollers.★ ● ★ ● ★ ●★ Each photo is taken in kind, but due to the difference in light, display and personal color, the color difference is small.