Twin Shower DoorRollers 25MM (2pcs top and 2pcs bottom).
The truck is held in place with a nut and this is covered with a chromed plastic cover
Easy Glide Eeplacement Shower Door Roller . From Picture Clearly see which Top /Bottom Roller
Glass Open-Hole: 12MM can be fit ; Pulley: 25MM GlassThickness: 4-6mm
These Rollers Fit 6mm Glass Shower Doors Where the Distance Between the Centre of the Fixing Hole and the Edge of the Glass is 18mm