New with seal, 14 treatments (28 strips) Crest 3DWhitestrips Glamorous White removes over 15 years of stains with a comfortable, no-slip teeth whitening experience. This enamel-safe, at-home teeth whitening kit will make your smile 8 levels whiter. Simply apply Crest 3DWhitestrips for 30 minutes a day for 14 days. This pack includes 28 teeth whitening strips, 14 for your top teeth and 14 for your bottom teeth, to be used over the course of 2 weeks.