Features: Make of iron material, it has corrosion resistance, wear resistance, and impact resistance, and can be used for a long time. These screws feature a detachable swivels designs, making installation and removal easily. These screws will work with standard sling swivels. Perfect for mounting a sling to your rifles. Designed for outdoor enthusiasts, photographers, and more, these swivels screws are suitable for people who uses sling swivels. Studs can be used with wood and synthetic bolts. Specifications: Material: Iron Size: As shown in the picture Package Includes: 3pcs/set Sling Swivel Screws note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.