Want to whiten your teeth at home? Crest 3DWhitestrips Professional Effects 1 Hour Express is designed for professional-level whitening at home. The Advanced Seal Technology ensures a no-slip grip, so you can talk and drink water while whitening. Made by the #1 dentist-recommended at-home whitening brand, it guarantees a 100% noticeably whiter smile. Using the same hydrogen peroxide ingredient as dentists, it makes your teeth 20 shades whiter. Simply apply 20 treatments for 45 minutes a day and 2 treatments of 1 Hour Express for 60 minutes. This pack includes 44 strips (22 for top and 22 for bottom teeth) for 22 days.