This is what Smashbox says: Smashbox Lash DNA Mascara contains a proprietary complex of proteins and amino acids that bind to lashes-creating mega-length and curl while conditioning and rebuilding former lash damage. The double-helix brush lengthens and separates every lash, no matter how small, for the ultimate fanned-out effect. This is what I say:) According to Smashbox, this mascara seems to be all about the brush and the brush is its most redeeming feature.It gives me lashes I want without any clumps. The brush works great to add a false lash effect. The brush has an hourglass shape but Still gets bigger on the end. I love that this mascara does not leave my lashes hard and stiff but rather soft and defined. I find that its also easy to remove this mascara from my lashes. I love using it in the evening. It also does not irritate my eye like other mascaras do.its very gentle and eye friendly:)