The kit comes with five pieces: three packets of mouthwash and two sets of upper and lower gel-coated styrofoam trays. You begin by rinsing with a mouthwash for 30 seconds, followed by placing one set of the upper and lower trays onto your teeth. After 25 minutes, the trays are removed, mouthwash is swished once more, and the tray and mouthwash process is repeated again.
Bonus points for ease of use and the low-on-the-messiness factor. Note: to prevent teeth pain associated with lightening, I brushed with a desensitizing toothpaste before and after the treatment, and had no issues with aches or sensitivity. I did, however, experience a wee bit of irritation on my gums, which are very irritable to begin with. But other than that, I was impressed with this low-cost, quick and easy way to get a whiter smile sans the neon effects.