The Penetraitt serum by Sebastian Professional is designed to smooth and repair hair. Its advanced formula penetrates deeply to mend hair damage, leaving it rejuvenated and styled-ready. Infused with hyaluronic acid and niacinamide, this serum targets internal damage for effective repair. Its professional-grade ingredients are perfect for reviving hair that is stressed, damaged, or color-treated, restoring softness and facilitating manageability as you sleep. You'll notice that upon waking, your hair feels softer, more flexible, and full of life - a fresh start for hair recovery. To use, dispense 3 to 5 pumps into your hand and apply from mid-lengths to the ends of your hair. Ensure even distribution and brush through, then leave it on overnight without rinsing or shampooing. Penetraitt Overnight Repair is a serum catering to fragile hair. Key advantages: a restorative serum for nighttime use on compromised and fragile hair.