Durable Material Fitness bearing pulley is made of high-quality nylon with steel bearing, durable and wear-resistant. Fitness Wheel Replacement Nylon pulley wheels are superb replacements for gym equipment and garage door pulley systems, easy to replace. Universal Bearing Pulley Wheel Universal pulley wheel hole inner diameter: 10mm, suitable for most gym equipment, home gyms, commercial or personal use. Features Nylon bearing pulley wheel, low noise, stable performance, and high load capacity. Small friction to ensure easy movement. Easy to Install Gym bearing pulley wheel is lightweight and easy to install. Specification: Material: Nylon, Metal Size Chart: Inner Hole Diameter: 1cm Package Includes: 1 Piece Fitness Bearing Pulley Note: Please allow slight errors due to manual measurement and different monitors.