Metal smooth bearing: The lower wheel adopts metal bearing, which is more stable and heavier. The concave wheel design is more consistent, the bearing shaft is smooth and round, and there are no scratches on the sliding. High quality material : Stainless steel panel, thickened panel thickness up to 1.5mm, thick material, not easy to deform, can be used in humid environment, durable anti-rust and corrosion resistant. < /p> Autonomous cleaning function: Each activity automatically cleans and refuses dust accumulation and stagnation, which effectively prevents dust from entering and is more durable. Suitable for kitchen cabinets and cabinets of different styles. Simple structure: Quick installation button, the upper guide wheel adopts copper button, the retractable upper wheel is convenient for door leaf installation. Cylindrical catheter, horizontal rotation structure, smooth sliding without jamming. Package includes: 2 sets of sliding door wheel kits, which can form two pulleys.