MACSTACK WATERPROOF MASCARA 0.4OZ. Benefits: Waterproof, smudge-proof, pool-proof and tear-proof, 24 hours. Clump-resistant. Weightless. Ophthalmologist tested. Appropriate for contact lens wearer. Features: Endlessly stackable mascara is now available in waterproof!. Featuring a smudge-proof, 24-hour formula that stays put all day. Stack on infinite waterproof layers of volume + length with MACStack Waterproof Mascara. Research Results: 96% said product stays put all day*. 96% saw instant lash lift and length*. 93% saw instant volume*. *Consumer testing on 109 people after using MACStack Waterproof Mascara for one week..