Ardell's Duo Brush-On Clear Lash Adhesive is a single-formula glue for applying standard strip, individual, or cluster lashes along the natural upper lash line -- a different, simpler product from Ardell's two-part Duo Bond & Seal underlash system, with no separate sealing step. It goes on white and dries clear, built on an acrylate copolymer rather than cyanoacrylate, and is formulated without formaldehyde or latex.
The clear formula includes small amounts of retinol, ascorbic acid (vitamin C), and tocopherol (vitamin E), included as conditioning antioxidants rather than active treatment ingredients. Application uses a built-in brush applicator for a thin, precise line along the lash band. As with any lash adhesive used near the eyes, a patch test before first use is a sensible precaution. If you're looking for the underlash bond-and-seal system instead, that's a separate Ardell product -- this one is strictly for standard strip-lash application.