When designing the new Fortis Super Lean Sport (SLS) FIFTY, they made sure the brand’s innovation, intent and quality were evident in every aspect of the design. While most AR safety selectors in the market today rely on standard socket/torx screws, the Fortis SLS FIFTY was engineered with the patent pending RidgeKey locking mechanism. This system allows the levers to secure itself onto the selector core with a solid point of contact and thus eliminating any weak points in the system. The selector core is coated in black nitride, giving you a smoother surface and superior resistance to wear. Never worry about the possibility of your screw backing out, breaking, or snapping with the Fortis SLS FIFTY.