Purple shampoo neutralises brassy yellow tones in blonde hair using colour theory, not bleach. The p80 Shade Enhancer Serum applies the same principle to teeth. A thin violet-toned layer counteracts the yellow undertones that make enamel look duller than it is, creating a visibly brighter, whiter appearance the moment it is applied. It is not lifting stains the way PAP-X does, it is correcting how the colour reads. Use it alongside any whitening routine, or on its own before a big moment when you need an instant lift.