S.M.
Crest Advanced Whitening Premium. The 10 day one. You can stop at anytime during it if your teeth get sesitive, and start again when you are ready. I don't smoke or drink coffee, but I love Green Tea and Red Wine. I, again, love my smile. By the way, the box says to leave on for 20 or 30 minutes, I would leave mine on as long as I could. The box is $20 at Wal-Mart. Good Luck!