Heavy Duty Quick Detach Sling Swivel With Enhanced QD Release Button And Angular Sling Attachment Wire-GGG-1419: 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.