The Inkey List Collagen Booster Face Serum - 30ml The Inkey Serum collagen booster for skin tightening Serum collagen in List (Inkey List) peptides called Matrixyl 3000 and Syn Tekt, which mimic the effect of natural collagen, and keep your skin look more smooth and silky for longer. The formula also helps to boost collagen production, so your skin will look firmer and more radiant in the long term as well. Reducing the appearance of fine lines and wrinkles and targeting sagging, this skin-enhancing dose is like a youth elixir for your skin: How to use Use it in the morning and evening on cleansed skin. Apply a pea-sized amount to the face and neck. Use fingertips to gently tap the serum onto the skin. It can be used alongside other serums and moisturizers as desired.