Space saving: make your room look more spaciousSuitable for cabinets, etc., smooth and silent operation, no slot ground wire clamped in the middle of the door or at the bottom of the doorSocket: Connect the rail and the cabinet with screws in the middleKeeper: Installed on both ends of the track to prevent the pulley from moving out of the trackEasy to match: It suits your home style, whether it's American Nordic Japanese or Rustic Modern MinimalistMaterial:Carbon steelcolour:BlackPackage Contents:4 x pulleys4 sets x anti-jump sheets4 groups x anti-blocking8 sets x screws (as shown)Only the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.