Beauty Hair Hair Products & Tools This Leave-In Hair Mask Is So Volumizing and Defining, I Wake Up With Perfect Curls Even in dire humidity. By Rachel Nussbaum Rachel Nussbaum Instagram Twitter Rachel is a journalist, writer, and editor who specializes in the beauty and wellness industry, writing about the best, safest products the industry has to offer for InStyle, Byrdie, and Shape. InStyle's editorial guidelines Published on July 28, 2022 @ 11:00PM 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. Photo: Courtesy R+Co Considering, you know, everything going on right now, I have never so badly wanted to curl up into a ball and hide under a rock. But for the sake of instilling positive change in this world where I can, I've begun volunteering as an abortion clinic escort. And because it feels nice to look fabulous while monsters scream in my face, I've taken to using my favorite hair mask every night prior to escorting, as a necessary self-care boost. The mask in question is R + Co's Cassette Curl Defining Masque, a new release the brand sent me as a gift that's made my life so much easier. It's since granted me countless of those shampoo commercial moments when you let your hair tumble from a bun into bouncing, defined curls. As a regular hair mask, it checks all the boxes: Chia seed oil, mango, and avocado butter add moisture, while rice protein strengthens tresses to counter damage and breakage. Washing the mask out after five minutes and following up with my regular styling routine leaves my dry hair shiny and luscious, but my favorite method is actually using it as a leave-in treatment. I was initially skeptical if it would deliver on the "defining" promise, but it did not disappoint; it's so hydrating, my ringlets resist poofing out and losing their shape — even in killer humidity. Courtesy Shop now: $38; amazon.com The phthalate-free fragrance is the cherry on top of this customer-favorite formula, with a mix of lemon, green tea, tangerine, and eucalyptus notes that the brand's dubbed "relative paradise" (relative, indeed). Since launching in June, the mask has earned raves from shoppers who are similarly impressed. One curly-haired comrade said they also love using the formula as a leave-in, especially because its lack of silicones makes it a fit for their curly girl hair method — and the results are "super soft." As a last user wrote, the mask amped up their hair's volume so well, their scalp is no longer visible where their strands were sparse and thinning. "I did not even need a styling product, and my hair has soft, bouncy, defined curls again," the fan wrote. If that sounds up your alley, get R+Co's Cassette Curl Defining Masque for $38 at Amazon.