Nite White® ACP now comes with 3 syringes per refill pack. All percentages have a mild mint flavor to them NOTE: 22% Bleach should only be used for a maximum of 1 hour per day, NOT overnight. NEW - Nite White is now shipping with the ACP (amorphous calcium phosphate) for maximum sensitivity relief formula - Try it today! All bleaching gel is stored in a climate controlled environment to ensure maximum results and longevity!