Wit Essential 16% Carbamide Peroxide Take-Home Gel Whitening Bulk Kit: 50 x 3g Individually Packed Syringes. Each syringe lasts up to 9 applications. 2 week treatment time with reduced daily use of 2 to 4 hrs. Close to neutral pH prevents demineralization and doesn't interfere on enamel and composites microhardness. Contains potassium nitrate and sodium fluoride for double desensitizing action. Gel has excellent viscosity with high water content to maintain tooth hydration.