This professional grade LIGHTWEIGHT semi-auto safety selector is the perfect upgrade to the AR-15. The CNC machined billet 7075-T6 aluminum skeletonized levers are strong and lightweight. It comes standard with a precision SWISS CNC machined reversible throw steel safety center core with 0-90 and 0-60 short-throw options. The standard and short aluminum safety levers are fully interchangeable and modular to accommodate left or right handed shooters.