FactorFive Eye/Lash Cream + Human Stem Cell Factors .5fl oz FACTORFIVE eye/lash cream combines human derived stem cell growth factors with biotin and redensyl. Growth factors help replenish a more youthful-looking eye area, where biotin and redensyl work together to quickly and safely enhance your lashes and brows. This particular product is unique in that it can be applied on both the lash line and around the eye area to promote collagen growth and thicker darker lashes.