The Timney 49'r Safety Selector can be used in either the normal 90 degree or for ultra quick changes a 49 degree short throw. It is precision machined, heat-treated steel, with a replacement spring and carbon nitride coated safety plunger for ultra-smooth operation. The safety features an end plate allowing the removal of the ambidextrous arm if a one-sided safety is preferred. The 49'r is a true drop-in part that will work with any Mil-Spec lower receiver. Made in the USA.