ITEM NAME:2pcs Standard Spinlock Dumbbell Bar Nut 2.5cm 1" for Barbells Collars, cast iron Description: Made of qualified cast iron with chrome plating- Anti-rust, high strength and anti-corrosion Designed for secures the position of dumbbell on the bar Easy and convenient installing/ removing To provide balance and stability safely and securely Inner Diameter: 2.5cm/0.98 inch; Thickness: 1.9cm/0.75 inch Package Includes: 1 Pair Dumbbell Nuts SKU: DMO0000569654046509.Designed for secures the position of dumbbell on the bar. 1 Pair Dumbbell Nuts.