[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 is equipped with a non-slip rubber ring, ensuring secure attachment to the barbell or dumbbell bar. [Package Content] 4 pcs x Dumbbell Spinlock Collars [Application] Perfect for use with bumper plates and lifting platforms. Also a practical gift for fitness lovers. Specification: Material: Iron with chrome-plated finish Size: 1 inch / 25 mm Color: Silver Note: Due to manual measurement, there may be a 0–2 mm error. Colors shown in the image may not fully match the actual item due to lighting and display differences. Please confirm you are comfortable with this before purchasing.