NIB Kiehl's Retinol Fast Release Wrinkle-Reducing Night Serum Kiehl’s is a heritage skincare brand trusted for its science-driven formulas that deliver visible results with high-quality ingredients. The Kiehl’s retinol fast-release wrinkle reducing night serum is a potent 0.3% retinol treatment that helps visibly reduce fine lines and wrinkles for smoother, youthful-looking skin. Formulated with 0.3% pure retinol to accelerate surface cell renewal Penetrates up to 15 surface layers deep for maximum effectiveness Reduces the look of fine lines in just 5 days* Improves the appearance of deep wrinkles in 2 weeks* Innovative packaging keeps retinol powder fresh until first use With continued use, skin looks smoother, renewed, and more youthful