Take-home Whitening for Custom Trays. • Custom whitening trays take a patient’s smile up to 8.4 shades whiter with virtually no sensitivity*• Contains potassium nitrate, which helps decrease sensitivity associated with bleaching• 3 strength levels available: 16%, 22%, and 35% Carbamide Peroxide.• Sticky, viscous gel is mint flavored for patient comfort• To keep teeth their whitest, Refill Kits should be used for touch-up every 6–12 months