Set of 4 shower door rollers - Two-wheeled (2 upper and 2 lower). Distance between glass shower doors and 2 glass holes: approximately 26 mm. High-quality chrome-plated coating. Roller diameter: 23 mm - Roller width: 5.5 mm. Minimum glass hole size: 11 mm. Maximum glass thickness: 6 mm. No noise - Smooth sliding - Easy to install and maintain.