Airtrim

Airtrim makes breathing masks for cold weather. The idea is simple: the mask protects your windpipe from cold, dry air. Air you breathe in through the filter is warmed and moistened by your own exhaled breath, so the chill doesn't hit your airways so hard.

That makes it a practical piece of kit for winter days outdoors. Airtrim says the mask lets you walk, train and stay outside for longer stretches in the cold without strain, which is the sort of thing that matters if you run, hike or simply live somewhere where January bites.

You'll find Airtrim stocked by Nordic outdoor retailers including Addnature and Outnorth, alongside other outdoor and adventure brands. It's an accessory rather than clothing, one to add to your winter bag.