The set includes one push-button-style sling swivel pin and one base for Picatinny rails. The quick-disconnect sling swivel is compatible with standard QD sockets. Simply push the button to detach and attach the swivel. The swivel pin has a ball bearing and rotates freely after being plugged in. For use with 1 1/4inch wide slings. Great for use on rifle stock or other Picatinny accessory rails. Heavy-duty alloy construction. Allen hex wrench included. Base length: 1inch Swivel set weight: 2 oz.