Dental Grade Professional Results in only 1 session. Guaranteed 4-10 shades whiter in less than 7 days. Features Hydrogen Gel Peroxide ( FASTEST IN THE INDUSTRY AND MADE IN THE USA) Use for 20 Minutes a Day Weekly Until Satisfied. Refills available online. Universal Comfort-fit tray provides full upper and lower whitening. Whiten even the toughest spots - removes coffee, tea, smoking stains and more. 10 times faster LED with built in timer.