New in Box RapidBrow Eyebrow Enchancing Serum. Sold as singles only, 2 available. Retails at $49.99 each. See my other listing for RapidLash. RapidBrow® eyebrow enhancer serum helps enhance the appearance of eyebrows. Youthful, flawless, healthy-looking, and absolutely beautiful brows become an achievable possibility! RapidBrow® Eyebrow Enhancing Serum is the best eyebrow serum specifically created cruelty free for eyebrows with an exclusive Hexatein® 2 Complex, a unique blend of fortifying proteins, stimulating peptides and nourishing key ingredients designed to help condition, enhance, and improve brow density and the appearance of eyebrow hairs as quickly as in 60 days. Try the best brow serum today!