Lancôme's Big Lashes Extension Fibers are numerous, ultra thin nylon loose fibers fill gaps between lashes to provide visibly fuller lash fringe and extend lash length. Lightweight and smooth for clump-free lash shaping. Spiral-Slim brush encapsulates fibers and delivers the ideal dose on lashes for bigger volume and length. Lash Extensions in a bottle. Bigger volume. Bigger length. All day wear.