The Nº.4P Blonde Enhancer Toning Shampoo, infused with patented OLAPLEX Bond Building Technology, is a highly concentrated purple shampoo that cleanses, tones and repairs with a sulfate-free formula that neutralises brassiness and boosts brightness after just one use. Application: Distribute evenly between palms first. Apply to wet hair and lather fully. Leave on for 1-3 minutes. (For more intense toning, leave on up to 5 minutes.) Rinse well and condition. For optimal brightening and hydration, use Nº.5P Blonde Enhancer Toning Conditioner from roots to ends.