Contains: 14 Applicator brushes; 1 whitening gel bottle (0.28 oz). Whiter teeth for up to 6 months. Dentist tested effective. Whiter teeth for up to 6 months. Crest Night Effects works while you sleep to give you a whiter smile for up to 6 months in just 14 nights. It releases peroxide, the same enamel safe ingredient that dentists use for tooth whitening. Crest Night Effects is dentist tested, enamel safe, and effective when used as directed. Visit your dentist regularly. Crest Night Effects is not a substitute for regular dental care. Brush from Ireland.