I had to write about this product because I have been using it for quite a while and cannot say enough about it. I have used just about every whitening product out there, including dentist bleaching trays and laser. I had been lazy to do it again the last few years because of the comittment of time, or pain( as in the laser. ) I bought these and I can easily commit to 5 minutes a day while getting dressed. It did take 2 weeks to see a noticeable difference, but after that they just get whiter and whiter. I get comments all the time on my teeth, and after using the product for about 2 1/2 months I now use it every other week to maintain the whiteness. I am thrilled there is something this easy to use, and I have no tooth sensitivity either. 5 minutes a day is sooo easy to do, you won't mind that it takes a couple of weeks!