The REN Flash Hydro-Boost Instant Plumping Emulsion is a water-charging hydration booster designed to work in harmony with the skin, to prevent the ageing effects of dehydration. Hyaluronic acid and Xylitol maximize moisture levels by helping to draw in water, locking it into the skin for an instant plumping effect. Long term use helps to reduce fine lines and prevent water loss from the skin. REN Clean Skincare is a PETA certified cruelty-free brand; they do not test any of their products on animals.