Get professional whitening results with Crest 3D White Whitestrips Intensive Professional Effects. To create your most glamorous smile, Crest Professional Effects strips penetrate beneath the enamel surface to whiten teeth. With 3D Professional Effects, you will start seeing whiter teeth after just one use. To use Crest 3D White Whitestrips Intensive Professional Effects, simply place the strip over your teeth once a day for two hours. These Crest Professional Effects strips offer a mess-free application and removal. The advanced seal also has a no-slip fit and no-fuss hold, so you can trust the strip to stay in place on your teeth while you handle other tasks in your day. These Whitestrips have a level five rating on the whitening meter, for your whitest smile yet. This package of Crest 3D White Whitestrips Intensive Professional Effects includes seven whitestrips, so you can see the full results after one week of use. Crest 3D White Whitestrips Intensive Professional Effects, 7 ct: * Gives you professional level whitening in just seven days * Five whitening power on whitening meter * With Advanced Seal No Slip technology * Enamel safe ingredients used * Includes 7 Whitestrips