Durable Material: Made from copper, stainless steel, and nylon with a bold copper shaft for wear-resistance and -free durability. Easy Installation: Use a screwdriver to loosen the old roller, fit the new one, and tighten the bolt for quick replacement. Stable Performance: Features good stability and a mute effect due to a small friction coefficient, suitable for curved doors. Versatile Application: Compatible with shower massage cabins, bathtubs, furniture fittings, and most shower rooms and steam rooms. Available Sizes: Sold in a set of 4 pieces with sizes ranging from 20mm to 27mm.