Includes 1 machine screw swivel stud and 1 wood screw swivel stud. Usually the machine screw stud goes in the forend and is backed by the nut (included) and shortened to fit. The wood screw stud usually goes in the buttstock. Install both studs to allow use of a sling with your rifle. Or, use only one stud in the forend to allow use with a Harris style bipod.