Made of material, durable and practical to useWear-resistant wheels with smooth and quiet slidingRotates to also fit curved and quadrant showersWheel diameter: 19/23/25/27 mm - Wheel width: 5/6 mm - Minimum hole size in glass: 10-14 mm - Glass thickness: 4-6mm.Package Content: 4 double bottom shower door rollersFeatures:*Premium quality product.Features:Quantity: 4 piecesType: shower door rollersMaterials: plastic, nylon, stainless steel and micro-bearing brass axleWheel diameter: 19/23/25/27 mmWheel width: 5/6 mmMinimum hole size in glass: 10-14 mm Glass thickness: 4-6 mm.Contents:Set of 4 shower door rollers.Note:1. The actual color of the product may be slightly different from the picture shown due to many factors such as brightness of your monitor.2. Due to manual measurement, the sizes shown may vary slightly.