iWhite Dark Stains is an easy-to-use teeth whitening product that is safe for your teeth and specifically formulated with Dark Pigment Adsorption Technology. This technology is based on the powerful and binding properties of encapsulated activated carbon micropearls. The one-size-fits-all trays are prefilled with active gel and hygienically packed. One packet contains 10 prefilled trays which are ready to use. This at home treatment should be worn for only 20 minutes a day for instant results, leaving your teeth looking up to 8 shades whiter.