Teeth Whitening System uses high-intensity blue light at a wavelength of 480-520 Nanometers. The light is filtered through over 30 layers of coated optical glass to remove infrared and ultraviolet light. Used together with our special whitening formula, the half hour procedure rapidly oxidizes 16 or more teeth through the dentin tube, restoring them to a beautiful white. Teeth Whitening operates at a lower temperature than similar products by using the latest optical techniques to avoid irritation of the nerves of the teeth. The 30-minutes process is very effective for teeth that have been stained by smoking or by substance like coffee or tea. It also whitens teeth discolored by medicine such as tetracycline or speckled by fluoride. Indication: It has good effect for the teeth that have been stained by smoking or stain-causing food and drinks, such as coffee sauce, tea. It also whitens teeth discolored by medicines, such as tetracycline, or speckled by fluoride. Whitens genetic