Usage Tips:[Quality Material]: Crafted from strength steel, these Dumbbell Collars are designed for durability and stability, ensuring that your weights remain securely in place during workouts [Secure Design]: Featuring a screw tightening mechanism, these Barbell Collar Clamps firmly lock weight plates in position, from any unwanted movement or slippage during exercise for a security and reliable workout experience [Material Composition]: Made of sturdy steel, providing long time performance and resistance to wear and tear [Product Dimensions]: Each collar has an approximate diameter of 2.5 cm/0.98 inch, making them suitable for barbells [Package Contents]: Includes two barbell collars per package, offering a complete set to secure both ends of your barbell effectively Specification: Material: Steel Size Chart: Diameter: 2.5 cm/0.98 inch Package Includes: 2 Barbell Screw Collar Note: Please allow slightly errors 1-2cm/0.39inch-0.79inch differences due to manual measurement.