Material:The barbell spinlock collars are made of high quality iron material, chrome plated, durable and corrosion resistant and can be used for a long time. Size: The anti-slip collar of the barbell 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 it can be securely and securely attached to the barbell or barbell bar. Package Content: 4 Pcs x Dumbbell Spinlock CollarsApplication: Perfect for use with bumper plates and lifting platforms. Also a practical and perfect gift for fitness lovers. Specification: Material: iron with chrome plated material Size: 1 inch 25 mm. Colour: silver. Package includes:4 x dumbbell spinlock collars. Please note: due to manual measurement, there may be a 0-2 mm error.The colours shown in the picture may not fully match the actual object due to the recording method and display device. Please make sure you do not mind before you buy, thank you Guaranteed:We are committed to providing you with the best service.If you encounter any problem during your usage experience, please contact us without hesitation.