The Olaplex No. 3 is a treatment for after the salon treatment that you apply to wet unwashed hair and leave it on for about ten minutes. Then rinse No. 3 and clean and care for your hair with the fine restorative shampoo and conditioner from Olaplex: No. 4 and no. 5. Do you want to further discover Olaplex because you have become so enthusiastic after the fine Olaplex treatment, or do you want to introduce someone else to the unique products? Then this set is ideal!