MDT 107320BLK: Perfect for adding weight and balance to your rifle.Adding weight to a rifle can cut down on recoil, allow one to self-spot their shots and balance their rifle. These weights mount on to the exterior of any chassis or stock that is M-LOK compatible. They mount using standard hardware and M-LOK T-nuts, meaning that you can install and remove them as necessary on your system. Each weight features a QD flush cup to accommodate a sling.