What it is: An endlessly stackable waterproof mascara, featuring a smudgeproof formula that stays put for up to 24 hours. Formulation Type: Volumizing, Lengthening Benefits: Long-wearing, Waterproof Ingredient Callouts: Free of parabens, formaldehydes, formaldehyde-releasing agents, phthalates, mineral oil, hydroquinone, sulfates SLS & SLES, and triclosan. What Else You Need to Know: This waterproof mascara delivers up to 24-hour wear with Drench-Defense Technology to resist smudging, tears, and humidity. Build endless layers of lash volume, length, and lift with this clump-resistant, flake-proof formula. It’s safe for sensitive eyes and contact lens wearers. Clinical Results: In consumer testing on 109 people, after using M·A·CStack Waterproof Mascara for 1 week: - 96% said product stays put all day - 96% saw instant lash lift and length - 93% saw instant volume