Loop End Plate Sling Adapter; For 4-position or 6-position CAR/M4 Stock; Will fit Sig 556 with collapsible stock. (Please note: Will not fit side folding units).; Work well in all types of configurations, including single point, two point or three point tactical slings; Easy, no gunsmith installation, no need for special tools or removal of buffer tube; Constructed of 6061 aluminum and hard coat anodized for a lifetime of service; Black Finish; Lifetime Warranty