- These Swivels Mounts onto most Standard Sling Studs found on most Hunting Rifles and Shotguns. To Unlock, unscrew out the knurled thumb nut, push in and rotate side arm 90 degrees to open sling swivel mount. Place bar through Sling Stud on long gun, rotate side arm over bar and screw in the knurled thumb nut to lock the sling swivel mount. Metal Construction, painted Black. Length: 1.25" Width: 1.6" outside width, (1.3" inside loop) Weight: 0.4 oz. each, (0.8 oz. total for both)