Material: Nylon and copper, offering good elasticity, wear resistance, corrosion resistance, and rust prevention. Stable quality with a long service life. Shower Door Rollers Size: Wheel diameter: 27 mm; wheel thickness: 5.5 mm. Compatible with 4–6 mm glass thickness. Total length: approx. 33 mm. Fits glass door openings of 10–12 mm (12 mm recommended). DIY Replacement: Easy to install and replace using a screwdriver. Smooth, quiet operation for effortless sliding of shower doors. Simple installation and maintenance. Mounts on the top and bottom of the shower door to ensure smooth opening and closing. Wide Application: Suitable for shower doors, massage cabins, bathtubs, Jacuzzis, and other furniture fittings. Compatible with most shower enclosures, shower cabins, and steam cabin enclosures. Package Includes: 8 rollers. Over time, rollers may require replacement. Ideal as spare or replacement parts.