The North Face Ventrix Hoodie (Women's)
This hooded midlayer was the warmest option in our roundup of the best women’s active insulation pieces. “I mountain biked in it one frost-crispened, 25-degree morning, and didn't once feel stifled, even during hard efforts,” wrote our tester. The Ventrix is built with temperature-sensitive fabric which dumps extra heat on the back and underarms.