42 strips: 21 treatments (each with 1 upper/1 lower). Whitens like a $500 professional treatment (vs. laser). At-Home No. 1 dentist recommended whitening brand. Whitens like a $500 professional treatment (vs. laser) with a comfortable, no slip whitening experience. Enamel Safe Whitestrips use the same whitening ingredient as the dentist. 100% satisfaction guaranteed. www.crest.com/whitestrips. www.pg.com. To learn more about Crest Whitestrips or get special offers, go to www.crest.com/whitestrips. Questions? Call 1-800-395-8423 or visit www.crest.com/whitestrips.