XTAR Dual light sources AA/14500 headlamp - Commander AA H1 1.Battery type recognition, different battery provides different output 2.Automatically shift down: When use lithium batteries,could switch to high from turbo automatically 3. Dual light sources, main light is for lighting and secondary light is for Signal use. 4.Click the switch to change between lighting modes. 5. Reverse-polarity protection to prevent damage from incorrect battery insertion