After 45 days of use in temperatures ranging from -10°F to 40°F, our tester declared the Synergy to be the ultimate helmet for making tracks in widely variable conditions. Credit a unique double venting system. Two front vents and eight small holes along the sides draw humid air from your dome to prevent sweat-out, while six larger, adjustable vents on top of the helmet allow you to customize flow to suit the weather. “The top vents are easy to open and close even with mittens on,” says our tester. “The fuzzy synthetic ear pads are warm enough for all but the most frigid days, and they’re removable, too, so I wore the same helmet for a full season of Colorado skiing.” $110; 1 lb. 1 oz.; (unisex 54-61cm); bolle.com
Gear Review: Bollè Synergy HelmetAn all-weather helmet with a unique double venting system.