This highly concentrated purple shampoo cleanses, tones, and repairs while keeping hair hydrated from roots to ends. A sulphate-free formula creates a rich lather to neutralise brassiness and boost brightness after one use for all blonde, lightened, and grey hair. Natural or stylist-created, root-to-tip or balayage, every client can benefit using this as part of their Blonde Maintenance Routine for the best blonde yet.Scientifically Proven:3x Brighter**Compared to top purple shampoosPRO TIP: Pre-wash with No.4 BOND MAINTENANCE SHAMPOO to remove any product buildup.To use: Apply to wet hair. Lather fully and let process 1-3 minutes. Rinse. For more intense toning, leave on hair up to 5 minutes. Follow with No.5 BOND MAINTENANCE CONDITIONER for everyday moisture or No.8 BOND INTENSE MOISTURE MASK for extra hydration.Where: Apply to wet hair, lather fully, and let process.When: 2-3 times per week or as often as needed to neutralize unwanted brassiness.For: All blonde, lightened, and grey hair.OLAPLEX products are thoroughly tested in-house and by independent third-party laboratories for safety and efficacy. This product testing includes the industry standard Human Repeat Insult Patch Test (HRIPT), which tests for skin irritation or sensitivity. All OLAPLEX products have passed the HRIPT, meaning the products show no signs of causing irritation, inflammation, or sensitivity.