[. . . ] [. . . ] Proper installation procedure by qualified personnel as outlined in the installations instructions must be adhered to. If installing the mount on other than wood studs use (commercially available) suitable hardware. Make sure the three knurl knobs are loosened to fully expose to the "tri-lock" mounting plate in the base of the upper assembly. Secure the rear safety knob (1) first to prevent further rotation of the bracket in the upper assembly. [. . . ] [. . . ]