Double Line Expert / LB-1 Extremely Thin Brown I bought this popular cosmetic, but I haven't had a chance to use it. From the official website: An extremely thin liner that fakes shadows around the eyes. Add a little line to make your eyes look bigger. How to use: 1. Incision line: Draw a line that extends from the inner corner of the eye. 2. Double eyelid line: Draw a line along the double eyelid crease. 3. Under-eye bag line: Draw a line under the under-eye bag and blend with your finger.