Features:The wheels are made of nylon with strong load bearing capacity. Good accessories and kit for home bathroom use.The pulley can be adjusted. Use a screwdriver to turn the screw clockwise or counterclockwise to shorten or lengthen the glass sizes.It is suitable to use in shower room, partition sliding door, sliding door.When you slide the door, there is no noise and slide smoothly.Easy to install and maintenance.Specifications:Material: nylonStyle: silver wheel upper wheelsilver wheel lower wheelsilver wheel upper wheelgray wheel upper wheelgray wheel lower wheelgray wheel upper wheelWheel diameter: 23mm (0.90inch)25mm (0.98inch)Note:Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.Package includes:1x Pulley