[Quiet] The wheels are made of nylon, which ensures wear resistance while taking into account the silence. [Waterproof] Fully enclosed bearing, waterproof and dustproof, not easy to rust.Extended service life. [Smooth] The wheel bearing is made of solid copper, which has a solid structure and strong bearing capacity, so that the wheel can slide smoothly on the track, which is very labor-saving. [Size]Wheel diameter: 20mm; Wheel thickness: 5.5mm.Glass door bore diameter:10~12mm.Suitable for 4-6mm glass thickness. Total length:33mm. [Easy to install] All you need is a screwdriver. Install the wheels on the top and bottom of the curved or straight glass doors., Weight: 0.440924524 pounds, Manufacturer: F Season