I bought this headlamp for camping/emergencies. Well I didn't have the opportunity to use it for camping before an emergency. Hurricane Sandy. I didn't have power for a month. I used this light nightly. At first I used it on high a lot. Within about a week I got the low power indicator so I began only using it on low beam power (which is really plenty of light). Well guess what I have never had to replace the batteries. I still have the original batteries from October of 2012 in there and on low power they have never run dry and the lumens stay consistent. This headlamp is a must have. I have actually bought a second for emergencies and keep this one by my bed for emergencies.