For the technical consumer who wants the best, brightest, most waterproof, feature rich headlamp to use for fast paced, extreme environment activities. This user also has the need to run the lamp on alkaline batteries if caught away from a power source for a long expedition. Dual-Fuel: Power with three AAA Alkaline cells (included) or the rechargeable BD 1500 Li-ion battery and charger (purchased separately) for maximum flexibility 450 Lumen max output IP67: Waterproof-Tested to operate at least 1.0 meters underwater for 30 minutes PowerTap™ Technology allows instant transitioning between full and dimmed power Brightness Memory allows you to turn the light on and off at a chosen brightness without reverting back to default setting Settings include full strength in proximity and distance modes, dimming, strobe, red, green and blue night-vision, and lock mode Multifaceted optical efficiency lens technology Black Diamond Storm 450 Headlamp