Beauty Hair This Viral Hair Mask Makes a Huge Difference In Just One Use Instant softness and shine? Yes please. By Erin Lukas Erin Lukas Instagram Twitter Erin is a Brooklyn-based beauty editor and has been with InStyle since 2016. She covers all facets of beauty for the site. InStyle's editorial guidelines Published on July 23, 2021 @ 10:30AM Pin Share Tweet Email We independently research, test, review, and recommend the best products—learn more about our process. If you buy something through our links, we may earn a commission. Between ponytails, coloring sessions, and hot tools, I'm not surprised my hair is often limp, dull, and dry. However, I'll admit, I'm a skeptic when it comes to hair products that promise to "reverse damage" or "repair" hair. Even if you don't color or heat style your hair as often as I do, natural causes like the sun and pollution can weaken hair and cause some breakage. Basically, we're constantly putting our hair through it. That's why when a treatment like K18 Leave-In Molecular Repair Hair Mask comes around, it goes viral. The product's patented bioactive peptides work to repair damage caused by chemical treatments and styling, and improves the elasticity and durability of hair. Since it's not solely directed towards color-treated hair, this mask is a product truly anyone can use. The "Expensive, But Effortless" Hair Color Celebrities Can't Get Enough Of According to the brand, the formula's polyeptides mimic the natural building blocks of the hair, so it's actually repairing each strand rather than covering up damage on a surface level. These changes happen with continued use, but expect to notice (and feel) a drastic improvement after a single use. I know I did. While this product is labeled a mask, you don't rinse it off. Instead, you apply it on freshly shampooed, towel-dried hair, leave it in for four minutes, then heat style or air dry, as you usually would. K18 recommends one pump, starting at the ends and working up towards the roots. As someone with straight, but very thick, frizz-prone hair, I need three pumps to fully work the product through my hair. After letting it marinate in my hair for four minutes, I like to brush it through my hair with a detangling brush before picking up my blow dryer. Courtesy Buy on Amazon Buy on Sephora I'll never forget the first time I tried K18, because I said "wow" out loud to myself in my bathroom. The mask made my hair so soft and shiny. I had just colored my hair a few days prior, and was riding out my blowout for as long as possible because no DIY blow-dry compares to just-left-the-salon hair. Sure, I can't tell whether the formula is doing anything for my hair internally just yet, but I'll take the instant gratification in the meantime. VIDEO: The Anti-Summer Hair Color That's Trending Now Suddenly, I'm looking forward to the next time I have to wash my hair. Good to Go used to be the column where we'd share the beauty products we can't travel without. But while travel's off the table, we'll be focusing on products that make us feel good in quarantine. This month, why I'm loving K18 Leave-In Molecular Repair Mask.