This professional-grade, no non-sense, duty grade semi-auto safety selector is the perfect upgrade to your AR-15. It comes standard with a reversible throw safety center with 0-90 and 0-60 short-throw options. The standard and short safety levers are fully interchangeable and modular to accommodate left or right-handed shooters. The new BAD-ASS-PRO is now 100% compatible with all known AR variant lower receivers, and triggers designed to work with the "Mil-Spec" AR-15 semi-auto safeties. No longer do you need a short-throw relief cut on your lower receiver to use the ambidextrous safety, simply use the provided short-throw markings sticker! No longer do you have to choose which trigger is compatible with the safety! If the trigger it will work with is a Mil-Spec AR-15 semi-auto safety, it will work with the new BAD-ASS-PRO!