Heavy Duty Quick Detach Sling Swivel With Enhanced QD Release Button And Angular Sling Attachment Wire: *Heavy duty components. *Large recessed QD release button. *QD Release button has custom CNC machined tactile grooves for more precise and more positive finger or thumb placement. *Heavy duty sling retention wire is angular shaped in order to place the HK style quick clips or mash hooks in the optimum position. *Manganese phosphated matte black finish per mil-spec.