The Breakthrough Clean Technologies® Armorer’s Wrench is the ultimate tool for your AR15/M4. Constructed out of durable titanium-plated stainless steel and includes a standard size muzzle device wrench. Easily installs and removes receiver extensions and castle nuts, functioning with both Mil-Spec and Pin-Style Barrel Nuts. Compatible with ½” Socket / Torque wrench and comes with a bonus Butt Stock Screwdriver.