In winter, dull is one — perhaps the nicest — way you could describe my hair. You could also opt for dry, frizzy, and void of life (just to name a few). When the weather turns cold, my already parched hair turns bone dry, promoting flyaways and frizz while leaving little to no shine. While leave-in conditioners and a mask here and there are often enough in warmer months, right now I could use a little extra help. Luckily, a hair serum Amazon shoppers swear by for making strands “soft and shiny” is now on sale for just $22.

Vitamins’ Keratin Serum, currently 27 percent off at Amazon, is a do-it-all product designed to nourish, moisturize, and strengthen hair while also protecting locks from heat, reducing frizz, and adding shine. It’s a big promise, but the nutrient-packed formula backs it up. 

Shop now: $22 (Originally $30); amazon.com

This serum includes several oils including moroccan, hydrating argan, strengthening castor, and smoothing coconut, which all work to soothe hair while adding fullness. And — as the name implies — it’s infused with the protein keratin for smoother, stronger strands. The brand also added a thermal heat protectant that keeps hair healthy and looking sleek when used with styling tools.

Given the serum’s breadth of claims, it has quickly become a shopper staple, with the 4,800-plus perfect ratings indicating that Vitamin’s Keratin Serum lives up to promises. “Finally, at 70 years old, [I] found a product that works,” wrote one shopper who described their once coarse hair as now “soft” and frizz-free despite living in a more humid climate. Another wrote that it saved their split ends, allowing them to grow their hair out while leaving locks “soft and shiny.” And while curly hair can be a little more finicky, one shopper wrote that the serum is a must for those “with curly hair that need frizz control,” explaining that it adds moisture and reduces frizz without leaving hair “feeling wet or oily.”

I want more than just the appearance of healthy hair, I want shine and strength, which is why I’ll be grabbing Vitamins’ Keratin Serum while it’s on sale for just $22 at Amazon — and you should, too.