Opalescence PF Mint 35% Teeth Whitening - 4pk Go to amazon.com Related posts Top 9 best opalescence strips FeatureOpalescence whitener 35% mint flavorColor chart includedShelf life up to 2 yearsEach syringe 1.2 ml DescriptionOpalescence 35% 4 syringes whitening gel. Color chart included. Shelf life up to 2 years. Each syringe 1.2 ml.