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: nylon Style: silver wheel upper wheel/silver wheel lower wheel/silver wheel upper wheel/gray wheel upper wheel/gray wheel lower wheel/gray wheel upper wheel Wheel 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