Made by pure brass.Very strong and durable.Can be used with confidence. Good performance.Corrosion resistant, high strength. It ensures quick and simple attachment of additional items to a suitable point on your scuba diving gear harness, weight belt or other equipment. Lightweight.It is very convenience to carry. Great accessories for underwater scuba diving, free diving, kayak boat paddle leash and so on. Description: Material: Pure brass Size: Approx. 54.2 x 23 x 11 mm/2.12 x 0.9 x 0.43 inch Color: Gold Quantity: 4 Pieces Single ended spring loaded bolt snap with large swivel eyelet. This product is easy to install and easy to use. Package Includes: 4 Pieces Swivel Bolt Snap Hook Note: Please allow a little size error due to manual measurement. Please be reminded that due to lighting effects and monitor's brightness/contrast settings etc, the item's color may be slightly different from the pictures. Please understand.Thanks!