Clinical tests prove that Oxylogy Blue LED light with peroxide whitens teeth better than peroxide alone. Enjoy that bright and confident smile you've always wanted for less the time and cost of conventional teeth whitening systems.According to The Journal of the American Dental Association, blue LED light is so powerful in teeth whitening that light alone whitens teeth 4.9 shades compare to 5.9 shades of Peroxide alone. When combined together (w/15% concentration), it whitens 8.9 shades.