420 lumens, focusing, rechargeable, auto-dimming, red light, Helmet buckles features make RH3 to be considered as a head lamp is for professionals. Whether you are camping, hunting, fishing, or you are part of the emergency services such as police, fire, ambulance, paramedic, mountain rescue, the RH3 won't let you down. High power-low power are the main function of RH3, but while your hands are occupied but still needs adjustable brightness light such as repairing, the auto dimming will help you. Red light on front emits a friendly light without disturbing your friends in camping. Red light on battery cartridge can be warning sign to avoid people hit you when you are walking or running on the road. The battery can be charged separately or inside of the lamp. 3 pcs of AA Alkaline batteries can supply power for the lamp when rechargeable battery is dead and there is no access for charging.