Opalescence Go 15% Hydrogen Peroxide Whitening Gel - Mint flavor. Kit: 10 Upper and 10 Lower Pre-Loaded Trays, Single Use. Wear only 15-20 minutes/day for 5-10 days. No impressions or custom trays necessary, ready to use right out of the package. Contains PF (potassium nitrate and fluoride). Whitening kit