Bump - variable power output. Low power battery lasts days, high power a few hours - and medium power which I used most about 12-18 hours before needing a charge. It’s a variable knob so you can adjust up and down to scan and then turn up the brightness when required. One hand operation, I had it velcro attached to my stock and easy to switch on/ off and power up or down without changing position.
On brightest beam it’s good for well out, I’d say 400m on a dry night. Manufacturer says 500m but I think they are over doing the sales pitch. Good lamp, tight beam.