The curved shower door roller is made of high-quality materials, anti-corrosion, sturdy and durable, with a long service life. Includes 8 curved shower door rollers with a diameter of 23mm: 4 top rollers and 4 bottom rollers. The fixed pulley of the shower door allows for easy one-click removal and cleaning. 23mm diameter curved shower door wheel fits glass doors 4-6mm thick. Upper and lower wheels are compatible with glass apertures of 12-14mm. The top wheel height is adjustable up to 8mm via stainless steel screws. The bottom wheel spring automatically adjusts based on the top wheel height. Shower glass door rollers ensure smooth sliding operation and quiet door movement. Suitable for use on curved shower doors in bathrooms, bathtubs, whirlpool tubs, and similar applications. Replacement shower door wheels include anti-collision blocks and mounting screws for easy installation. Color: silver Material: plastic Package Contents: 4 pairs x pulleys 8 x anti-collision blocks 8 x screws Note: This package includes only the items listed. Other products are not included. Note: Lighting and display differences may cause slight color variations between the image and the actual item. Measurement may vary by +/- 1-3cm.