Ha is a natural biotic component , widely existing in skin and any other tissue .It has outstanding moisture keeping ability , thus called natural moisturizing factor (nmf) in the world .It is the best component used in cosmetics for moisture keeping in the nature . When ha applied to the skin, macromolecular ha can form an air permeable thin layer and keep the skin smooth and moist, and protect the skin from bacteria, dust, and ultraviolet ray. Ziyan is one of our brand , this hyaluronic acid can be directly applied to the face which can hold 50 to 500 times of water .The collagen in our skin will losing with the time goes by, but the rate of loss is inversely proportional to the hold of water.So if you use our purducts for a long time you will feel the effect, your skin will be very smooth and much white. 5ml/bottle