best serum for eyelash To define your brows, start with the proper eyebrow tools and products. We recommend our Dual-Ended Brow Definer/Groomer Brush and our Brow Kit or an eyebrow pencil to add the definition that helps your brows stand out. First, brush your brows out using best serum for eyelash: a spoolie to see your natural brow shape. Then fill any sparse areas and gaps between hairs by drawing hair-like...