Geek & Gorgeous 101 C-Glow 15% Vitamin C Serum 30ml New Best By 07/2023. I ship very fast generally on the day of purchase. Vitamin C is a clinically proven active that gives the skin Environmental Protection as an antioxidant, boost collagen production and Fades hyperpigmentation. This water light formula contains 15% vitamin C and extra antioxidants to give a healthy glow even and firm the skin.