Benefit Cosmetics Hubba Brow Brow Enhancing Serum in Beauty: NA. Benefit Cosmetics Hubba Brow Brow Enhancing Serum in Beauty: NA. Hubba Brow serum improves the appearance of brow volume in just 4 weeks and shows fuller-looking brows at 12 weeks. The gentle formula contains a custom blend of vitamins, plant extracts and rice protein, is suitable for sensitive skin, and feels comfortable on brows. Brows look healthier, natural, and nourished over time. Plus, the wand features a flexible microbristle tip.. Suitable for sensitive skin. Cruelty-free. 4.5 g. Apply nightly to clean, dry brows. Let dry before applying skincare products.. Turn up the volume with Gimme Brow + volumizing fiber gel (sold separately).. BCOS-WU535. BM257. Founded in 1976 by a sister duo of San Francisco beauty lovers, Benefit seeks to bring laughter and fun to the world of cosmetics. Guided by the mantra makeup doesn't have to be serious to look good, Benefit's iconic products boast breakthrough formulas in loud, playful packaging, inspiring women all over the world to apply more lipstick, grab life by the giggles, and fake it 'til you make it.