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Alongside Hailey Bieber, we’re huge fans of everything Kosas creates (the supermodel loves the brand’s concealer and setting powder.) Naturally, when we caught wind that the beauty company was launching its own growth serum for the lashes and brows, we sat at the edge of our seats in anticipation. Well folks, today the soon-to-be bestseller has officially launched on the Kosas brand site and Sephora.

The 2-in-1 formula is no regular growth serum; it’s packed full of highly effective ingredients that provide real, visible results in as quick as three weeks—no really, through a clinical-run study, 97 percent of users saw improvement in both brow length and lash volume during that time period. 

Kosas GrowPotion


Kosas Grow Potion Fluffy Brow + Lash Boosting Serum

Credit is due to four key inclusions: a trio of peptides that support length and thickness; vegan keratin for nourishing and strengthening the hair; pro-vitamin B5 for optimal shine; and hyaluronic acid for hydrating and conditioning. Plus, those with sensitive eyes can rest assured the formula is completely hypoallergenic, ophthalmologist-tested, prostaglandin-free and fragrance-free.  

Buzz is already building for the newly released product; one Sephora shopper referred to it as “truly amazing,” after witnessing fast changes with their hair. “Now, did it help my lashes and brows grow? YES, it sure did,” they wrote. “Using this for a little over a month now, I see great and new growth on my brows where hair was sparser, and my lashes look longer. I would highly recommend for anyone looking for a great lash or brow serum, it does a great job!”

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To tap into the serum’s transformative powers, simply swipe the applicator across the brows and on top of the lash line once per day, making sure to avoid the inner corner, waterline, and bottom lashes (the upper application ensures the lower lashes are covered, per the brand.) Consistency is key here; skipping applications will only delay your results. It’s also advised that you wait for up to two minutes for the serum to set before applying makeup.

“I have been a licensed Esthetician for over four years and a Registered Nurse for over 30 years and am always looking for products and cosmetics to improve my personal appearance as well as my skin health…I noticed results after using [the serum] for one week in the evening. I have been looking for something that will help my eyebrows to thicken, and this product will not disappoint,” raved another reviewer.

It’s the perfect pairing to Kosas’ Air Brow Gel—except it brings “six times more powerful and effective hair-boosting actives in a concentrated serum,” says the brand. Apply your Air Brow Gel in the morning, and lean on your GrowPotion come nighttime to unlock your fluffiest brows and lashes yet. 

Stock for launches like these don’t tend to last long, so pick up your own growth serum for $48 on either Kosas or Sephora while you still can. 

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