If you want to cover up pimples, birthmarks, or other unwanted things, then a concealer is the way to go. This product is waterproof, which is very handy during summer.
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Juvia's Place I Am Magic Travel Size Liquid Concealer - Full Coverage Concealer, Hydrating Concealer, Waterproof Concealer, Long Wear Concealer J18 (Medium-Tan with Golden Olive Undertone/0.11 fl oz)