Got this product at a discount because of a code offered. Retail was $99 I believe. Mine has 3 treatments in 1 box, used 1 treatment so far. It kind of burned a little because of my sensitivity but my teeth got 2 shades whiter in just 1 use. Pretty good for what I paid, I wouldn't say it would be worth the $99. Extremely messy though after the 20 minutes of holding the gel on your teeth.