I bought this unit experimentally for a rather unusual purpose. I suffer from macular degeneration, and although my peripheral vision is reasonable, focusing in on small areas is a big problem, e.g. in the kitchen setting cooker knobs, and various other close-in household jobs, and in trying to obtain enough light when struggling to read or write, or do my favourite 'Codewords' puzzles etc.
I could not have made a better decision. What a difference this little unit makes in many of the difficult situations I face with my deteriorating eyesight. Firstly, it arrived with Amazon's usual promptness. When set up, it provides excellent beam strength adjustment for anything I throw at it, and the 90° vertical adjustment allows for precise positioning. The headband is well made, lightweight, adjustable, and very comfortable to wear. The only thing on which time will tell is battery life, but as I most often use it on the lowest level with one LED, I have little fear of this being a problem. And although it comes with 3x AAA batteries, I may well decide to get rechargeables.
For anyone else who has similar eyesight problems to mine, I can thoroughly recommend this unit.