Read the packages and check the contents
These whitening strips seem to work ok - I was able to get a couple of shades whiter after using for two weeks.  I don't think all the strips were there and I wish I would have counted the contents of the packager.  I accidentally used the fast acting strips not realizing they were different as the packages look very similar.  I do think they work just wonder how the actually compare to name brands that I have not used.  I used the watermelon flavor and it was not bad.  The strips stick really well when following the instructions.
Rating: 3 stars