Olaplex no.4d clean volume detox dry shampoo is an innovative, volumising style extender with ingredients that support a healthy scalp. It's a dry shampoo, the olaplex way. No.4d clean volume detox is a dry cleansing formula with skincare science inspired ingredients to detoxify and maintain scalp health between washes. After all, the scalp is skin too and the root of clean, healthy hair is a clean, healthy scalp. Cleanse. Repair. Detox. Key benefits detoxifying and soothing to cleanse, calm and maintain a healthy scalp. No buildup oil absorption for a just washed clean hair feeling. To use shake well before using. Separate hair into sections. Hold the bottle 6 10 away from the hair and spray onto the roots. Wait 30 seconds and massage into the scalp. 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.