For those of us who need a cassette adapter, this one works. I never had luck with FM transmitters. To be specific, It worked fine, out of the box, for a couple of weeks of infrequent use. Then we used it on a car trip and after about 2 hours of total use it started spitting out after trying to auto-reverse. It would not play after that. A known problem, I followed online help to try to fix it but it still didn't work. Then I found a tutorial with pictures which I realized I was putting the 2 tiny springs back in the wrong way. Finally it is working! I give it only 3 stars because I shouldn't have to do what I did to get the product to do what it is supposed to do. They should not even put the auto-reverse piece in the product. A link to the helpful pictures: [ ... ]