Received my headlamp, loaded the batteries, donned it, and tested it. About 2 days after receiving the headlamp we had a power outage due to severe weather. Fortunately for me, I had my new headlamp. Used it for the first time, albeit unexpectedly. Worked great and got me through the couple hours of darkness until power was restored. What did I do while the power was out? I used my headlamp to read. This is a great product. Recommend it for anyone needing to work in dark spaces or for night running or hiking.