Ardell Double Up Duralash Knotted Double Flares Individual Lashes Long Black have twice (2X) the number of lash fibers per individual cluster and are perfect for lash wearers who want to customizes their eyes with thicker lash volume. Ardell Professional 56 Double Flares Knotted Long Black individual lashes contain 20 strands of lashes per individual lash cluster compared to 10 strands in the regular knotted ones for more dramatically intense eyes.