The Real Avid Magnetic Bore Light is ideal for illuminating hard-to-see areas. The bright white LED puts out15,000 mcd brightness from a 5 inch flex neck which positions light onto hard to reach areas. It runs for nonstop for 8 hours. The light requires three LR44 button cell batteries. An integrated magnet lets you attach the magnetic bore light to any steel part of your gun for hands free use.