We know, you know, but we'll say it again for good measure: Amazon's biggest shopping event of the year, Prime Day, is finally here. While there are tons of cart-worthy beauty deals on popular makeup brands and top-rated skincare formulas to be had, this page is dedicated to the best Amazon hair products you can nab during Prime Day's two-day event. We're talking markdowns on goods that will make every day a good hair day: from 20% off Act+Acre's scalp-detox serum to Bio Ionic's iconic styling iron, 25% off Fekkai's cult-favorite volumizing shampoo, and 30% off Living Proof's editor-approved dry shampoo.