The first time it worked flawlessly but the next day nothing. (Here's where a serial negative reviewers would grab their smart phone and post a scathing one star butt hurt review.) I thought it's probably the battery and when I pulled it out it wasn't bright and shiny as button cells usually are. Oh well no problem I had a couple fresh new Duracell CR2030s I just bought for a rifle scope. I popped a new battery in and the tuner came right on and we were back in business with no harm done. It was responsive and the display was bright... for about 2 minutes then it slowly dimmed down to nothing. The next time I tried it the tuner came right on but wasn't as bright and dimmed down to nothing in about 30 seconds. I pulled and tested the battery and seeing it was okay tossed the tuner in the trash. So if you're wondering why does it deserve two stars it's because at $10.45 I didn't pay much and quite frankly I didn't expect much. Since I got exactly what I expected I wasn't offended and am moaning and complaining that I was ripped off, cheated, sold crap and Amazon was out to get me... through no fault of my own.
Don't get me wrong, I hoped it would work because I planned to pass it on to my grandson and it wouldn't be a big deal if he lost it or broke it. Moreover, based on the number of happy 5 star reviewers I probably got one of a very few defective tuners that slipped through.Over my lifetime I have always bought the very best I could afford and if time permitted I'd wait in order to get something better. Fortunately cost is no longer a factor but I went ahead and bought something my gut told me not to. Hopefully this tuner will work for you, but if it doesn't not to worry because life goes on and there are more important things to fret over. Which reminds me, I've got to smooth that nick between A and D on the 5th fret.