The Auto-Dimming Headlamp features the latest in battery lighting technology! The patented auto-dimming sensor instantly adjust the light’s brightness to the user's environment. Beam instantly becomes brighter when user looks at objects far away, automatically switches to low output when user looks at objects in very close range. The function helps to reduce glare found from using a standard headlamp being too bright to use for close range illumination. The function helps to extend battery life by efficiently using power.