Shower Door RollersSet of 4 shower door rollers. 25mm diameter bathroom DIY spare parts (2 upper rollers and 2 lower rollers), each wheel comes with a bumper and a screw in stainless steel. Perfect ExperienceMaterial of sliding door rollers: High Quality Nylon Wheel + Copper Core Shaft, Low noise, elegant performance and rolling smoothly, Suitable for 4-6 mm glass thickness. Exact SizeShower Door Installation Kit Roller Diameter 25mm. Wheel thickness: 5mm, shower door thickness: 4-6mm, glass mounting hole: 12-14mm. Easy to UseEasy sliding replacement shower door roller, easy to install and use, with these sliding door pulleys, the shower door will glide like butter. Super functionShower door rollers suitable for most shower enclosures, shower enclosures and steam cabins. Set of 4 twin shower door rollers. ( 2 upper rollers and 2 lower rollers ) Material: copper swing + electroplating plastic alloy. Wheel diameter: 25MM. Wheel thickness: 5 mm. Glass mounting hole: 12-14 mm. Glass thickness: 4-6 mm. Easy installation, often used for bathroom sliding glass door pulley/track. Fits most shower doors. Note: Please measure the dimensions for better installation before purchase. Upper pulleys The height of the upper pulley can be adjusted by turning the screw with a screwdriver. These shower door wheels are suitable for 4-6mm glass thickness and 12-14mm glass opening, there are 4 extra anti-collision blocks to give your shower door the best protection . Lower pulleys The lower pulley is a stainless steel sealed bearing. It can be adjusted according to the height of the last lap. Packing List Contains 2 upper rolls and 2 lower rolls. Each roller is equipped with an anti-collision block and a stainless steel screw. How to replace the pulleys? Step 1: Remove the decorative cover, loosen the screw and remove the old lower pulleys. Step 2: Once the lower pulleys are removed, lift the sliding bathroom door and remove it. Step 3: Loosen the screws with a screwdriver and replace the upper pulley with a new one. Step 4: Lift the glass door and place the top pulleys into the track. Step 5: Use a screwdriver to adjust the height of the upper pulleys to the highest point. Step 6: Install the lower pulleys and place them in the track. Step 7: Mount the anti-collision blocks on the rail to prevent the glass from colliding.