???30-Day Manufacturer Guarantee?- Come with 30 days guarantee and friendly service, if our vitamin c serum doesn’t work for your skin, or you simply don’t like them, the item can be returnable. We guarantee you a pleasant shopping and using experience. ???Safe for All Skin Types?- All of our products are cruelty-free, dermatologist-tested, and made for all skin types and tones. Plus, they're packed with thoughtfully-chosen ingredients you can feel good about. ???Directions?- Directions: Apply Vitamin C Serum in the morning and night. Apply 3-5 drops to clean, dry skin on face, neck. Use sunscreen daily, as retinol increases sun sensitivity. ???Advanced Antioxidant Serum?- Vitamin C blends with Botanical Hyaluronic Acid and Vitamin E, Retinol, Nicotinamide, designed to target the most common signs of aging, including firmness, fine lines, wrinkles, dark spots & sun spots. ???Brightening, Firm and Dark Spot Remover, Reduce Wrinkles?-In a study of 98 users, 97% had smoother skin in 3 weeks, and 92% saw more brightening after 2 weeks, 87% saw Dark spot reduction after 4 weeks.85% saw Wrinkles reduction after 6 weeks.