The OLAPLEX No. 4P Blonde Enhancer Toning Shampoo is a highly concentrated purple shampoo formulated to brighten, tone, and strengthen blonde, lightened, and gray hair. Infused with the brand’s patented Bond Building Technology™, this sulfate-free formula neutralizes unwanted yellow and brassy tones while actively repairing and protecting fragile strands. It delivers powerful toning results without drying out the hair, leaving it soft, shiny, and vibrant. With each use, blonde hues appear cooler, cleaner, and more luminous, making it the perfect weekly treatment for maintaining salon-fresh color and healthy, resilient hair.