Works, but some parts are cheaply made
Overall the product is easy to use.  I did see good results in terms of the whitening.  I drink coffee a lot and I could tell the difference in whiteness after four sessions.  So, it works for me.<br /><br />The bad.  The battery that hangs on your neck is totally cheap and flimsy.  The connection on mine where the mouth guard clicks into it was so cheap that I had to keep checking as the light would suddenly go out.  I had to twist the guard plug to get it to light up again.  If they made this just a little nicer I would give this 5 stars.
Rating: 4 stars