Precision Machined from 6061-T6 Aluminum and Finished in Matte Black Anodize. Mounts Bidirectionally in One M-LOK Slot on in Between Two Adjacent Slots. Quarter-turn Rotational Over Travel Stops Prevent Unintentional Sling Swivel Rotation Resulting in Sling Entanglement. Accepts Any Quick Detach Sling Swivel with 0.37” Diameter Swivel Stud. Includes M-LOK T-Nuts, Screws, and Assembly Tool for Simple and Friendly Installation, No Gunsmith Required