Features: The wheels are made of upgraded polyurethane. The texture is light and soft, the toughness is particularly large, which is not harmful to the human body and the environment. Upper and lower raceways filled for w/ high-quality swivel bearings that enables the caster to rotate 360 degrees smoothly, swiftly, and silently. The powerful double locking action keeps the wheels rolling and spinning freely when unlocked and keeps the wheels stopped and secure when locked Swivel easily under full heavy load and rolls smoothly without dragging or jamming, the max capacity of 4 wheels is up to 1200lbs The wheels can be used for a multitude of applications Including: Flight Cases, Instrument Cases, Tool Boxes, Light Machinery, Equipment Stands, Mobile Workstations, Speakers,Display, Furniture etc. Specifications: Material: PU Size: 1.5 inch /2 inch Type: 14 optional Package Includes: 4 Pcs/Set Heavy Duty PU Castors. note: Please allow 0-1cm error due to manual measurement. Make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!