What is it? Ardell Duo Eyelash adhesive is the world's best selling waterproof lash adhesive. Ardell Duo Dark Individual lash adhesive is made for individual lashes. The dark shades blends naturally with dark lashes for a flawless look. What makes it special? Blends with black or brown lashes Convenient dropper bottle Waterproof Pour 2-3 drops of Duo Individual Lash Adhesive onto small piece of foil. Gently grasp a single lash with tweezers near knotted end and pull from tray. Dip knotted end of lash into adhesive. Place lash on top of your natural lash with the knotted end as close to your eyelid as possible.