Potent Vitamin C is clinically proven to have anti-ageing benefits. Medik 8 CE-Thione helps protect the skin against free radicals (the main cause of photo-ageing), while minimising the formation of dark spots for a visibly brighter skin tone & an enhanced texture & firmness. Unlike any other Vitamin C serum, Medik 8 CE-Thione uses Medik 8's trademark Rechargeable Vitamin C™ concept to ensure every drop of Vitamin C in the serum is fresh & highly potent, ensuring you get the results that Vitamin C can deliver. The special formula mimics how the body naturally keeps Vitamin C stable in the skin. The Vitamin C is 'recharged' by having two antioxidant 'allies' in solution with it: Vitamin E & L-Glutathione which then regenerate the Vitamin C molecule when it is used up, delivering an incredible potency.