Material: ABS + zinc alloy. Supplied with screw cover. Easy to slide and clean.Dimensions: suitable glass thickness: 6-8 mm, diameter of the wheel: 26 mm, diameter of the hole in the glass: 10-14 mm.Screw caps: the truck is held in place with a screw and this is covered with a chrome plastic cover which makes it pleasant to the eye and easy to clean.Field of application: suitable for sliding shower doors flat and sliding shower doors.Set of 4 upper shower door rollers and 2 shower door rollers."Features:Color: As the picture shows.Material: ABS+Alloy of zinc.suitable glass thickness: 6-8 mm.Diameter of the hole in the glass: 10 mm -14mm.Wheel diameter: 26mm.The center of the glass hole to the bottom of the glass: 15-17mm.Contents:2 upper pulleys.2 lower pulleys.4 protection blocks.4 screws.