Keep your aligners and retainers odor-free, hygienic and clear with the Invisalign Cleaning Crystals. Special Cleaning Crystals remove plaque from aligners and retainers in about 15 minutes. Contents: 50 packets of Invisalign Cleaning Crystals. Storage: Store crystals in a cool, dry place. Ingredients: Sodium Sulfate, Sodium Carbonate, Sodium Tripolyphosphate, Sodium Dichlorosocyanurate, Sodium Lauryl Sulfate.