your outerwear The system starts next to the skin. Your undershirt (known in the outdoor industry as a “base layer”) should be comfortable, unobtrusive, and wick sweat away from the outer layers of clothing so you don’t stay wet. Getting wet can be just annoying, with the discomfort of shivering and chafing, or it can be downright deadly if you’re in cold weather conditions.
Two things we look for in a base layer are how light it is and whether or not it has a lid. The latter is not necessary, but it is very suitable on sunny days. There are plenty of undershirts and base layers; A few of them are awful, but a few really stand out, too. This is our favourite.
Updated November 2021: We’ve added Ibex Woolies Tech Crewe and replaced Mountain Hardwear’s margarine with a Ghee Zip-Top.
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