I am selling this item because I purchased and opened it at the end of November but no longer use it. I've used it about 5 times, but the amount used each time was small, so it's hardly been used. You can mix it with your existing oil-based base to make beauty oils or creams. This is a vitamin C derivative, famous for its firming and antioxidant properties. Among them, oil-soluble vitamin C derivatives are vitamin C derivatives that dissolve in oil, so they blend with the skin's oils and penetrate, exhibiting high effectiveness. Since it can be mixed with oil, you can achieve the moisturizing effect of oil, as well as address pore care and improved transparency. Example of use: Add 0.25-2.5g of this product to 50ml of oil or 50g of butter. Vitamin C derivative. For the raw materials of homemade creams. Homemade cosmetic raw materials. Contains 50g.