Each of the hair tool deals listed here for Prime Big Deal Days is a gadget that's been vetted for our Best Hair Straighteners, Best Diffusers, Best Hair Dryers, Best Blow-Dry Brushes, and Best Curling Irons guides and deemed worthy of purchase by our Reviews team of testers, as well as tracked over the previous weeks to ensure the sale is a legitimate one. For deals on other gear we like, check out our Absolute Best Deals roundup and our liveblog. Cut your styling time in half.