Package includes: 4 double upper rollers and 4 singel bottom rollers, in total 8pcs Comes with screw cover caps. Spring loaded action can also fit curved showers. Designed with a nut and a plastic cover. Material: Plastic, Nylon, A Plastic, Nylon BS and stainless steel Diameter of the wheel: 22mm; Width of the wheel: 6mm. Minimum Hole size in the glass: 11mm. Maximum glass thickness: 6mm 8 pcs Double Shower Door Wheels
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