Description Color: silver, gray Size: Diameter 23mm Material: nylon + stainless steel weight:45g90g Specifications: 1*upper wheel, 1*lower wheel, 1*upper wheel+1*lower wheel describe: Plated door roller: 23mm (diameter) roller top bottom shower door roller, plate surface, anti-rust suitable for glass doors with thickness of 4-6mm, glass opening is 13.5-14mm. (recommended for 14mm glass hole). These replacement shower door rollers fit most shower, shower and steam room enclosures and fit on the top and bottom of the shower door, making it easy to open and close. (recommended for 14mm glass holes). Opening the shower door makes no noise and these glass door rollers help it slide smoothly. It is easy to install and maintain. (14mm glass hole recommended).