The Noveske Universal Sling mount is a push-button flush cup sling mount designed for installation in hollow polymer buttstocks, forend, and other non-standard applications. The swivel's flush cup is rotation limited in four positions so your slings will not become twisted. Installation of the mount requires a 1/2" hole to be drilled into the stock in a flat area, then using a push-button swivel as a driver thread the flush cup into the backer nut. Permanent thread locker, like red Loctite, should be used to ensure a solid installation. This mount will work with stocks that have a thickness of 1/4" or less. Notes: Requires permanent modification of the stock or foregrip (drilling 1/2" hole)Permanent thread locker needs to be used Flush cup is rotation limited