Material: The barbell spinlock collars are made of high-quality iron material, chrome-plated, durable and corrosion-resistant for long-term use. Size: The anti-slip collar is suitable for 25mm standard barbells or dumbbells. Please check the size before purchasing. Anti-Slip Design: The barbell clamp features a non-slip rubber ring to ensure secure attachment to the barbell or dumbbell bar. Package Content: 4 pcs x Dumbbell Spinlock Collars Application: Ideal for use with bumper plates and lifting platforms. Also a practical gift for fitness enthusiasts. Specification: Material: Iron with chrome-plated finish Size: 1 inch (25 mm) Color: Silver Package Includes: 4 x Dumbbell Spinlock Collars Note: Due to manual measurement, there may be a 0–2 mm error. Colors shown in images may differ slightly from the actual product due to lighting and display variations. We are committed to providing excellent service. If you have any issues, please directly.