Supports all 2 inch Olympic barbells. Kobo 2 inch dumbbell spring clamp is suitable for standard 2 inch smooth weight bars, curved bars and dumbbell handles (without thread). Quality Material: We use high-quality steel structure design, with high functionality and durability, making the gear durable, not easy to rust or break. Features: Easy to Install: The barbell clamp is easy for you to use, can be quick to slide into the place and off the bar, provide you a firm support and grip for your barbell, help to hold bumpers in place, protect the heavy objects from falling off and avoiding to hurt you or break the floor, make you do sports safely and confidently, very practical for training lovers. -High Utilization Rate: People who exercise and fitness will often use barbell spring buckles. -Suitable Occasions: The dumbbell spring collars are suitable for home, gym and outdoor activities, can be applied for workouts, overhead press, weightlifting and more sports. Specification: Material: Steel. Color: Silver. Size of Each Spring Collar's Hole: Approx. 50 mm/ 2 inches in diameter. Quantity: 2 Inch Dumbbell Spring Clip Collar (pack of 2).