High quality POM plastic construction. Compatible with various shower door types, ensuring a smooth and comfortable sliding operation. Ideal replacement for damaged or worn rollers, providing a cost-effective solution to restore functionality without replacing the entire system. Suitable for use on shower doors, massage cabins, bathtubs, jacuzzis, and other sliding door applications. Features fluid bearings that enable effortless forward and backward movement, evenly distributing glass weight and maintaining controlled motion for enhanced durability. Each set includes four rollers with 20 mm diameter wheels and 5 mm thickness, designed for shower doors 4 to 6 mm thick. Wheel core made of copper with stainless steel components, including M4 mounting screws. 9 mm diameter steel axle, 3 mm height. Pulley equipped with precision bearing for smooth, quiet operation, low friction, and high stability. Resistant to corrosion and rust. Easy to install and commonly used for bathroom sliding door applications.