What's included: 4 double shower door rollers (2 top, 2 bottom). (recommended for 14mm glass holes, not suitable for glass holes less than 13mm) Plated door roller: 23mm (diameter) roller upper and lower shower door roller, surface plating, anti-rust ; suitable for glass doors with a thickness of 4-6mm and glass openings of 13.5-14mm. (14mm glass hole is recommended, not suitable for glass holes smaller than 13mm) These replacement shower door rollers fit most shower, shower and steam room enclosures and Fit at the top and bottom of the shower door for easy opening and closing. (14mm glass hole recommended, not suitable for glass holes less than 13mm) Opening the shower door makes no noise and these glass door rollers help it slide smoothly. Easy to install and maintain. (14mm glass hole is recommended, not suitable for glass holes smaller than 13mm) The shower door double rollers are easy to install, please determine the size of the rollers you want and the diameter of the glass hole . (14mm glass hole is recommended, not suitable for glass holes smaller than 13mm)