If you're heading off skiing, regularly walk in cold conditions, or suffer from Raynaud's, you need to know about heated socks. Just like a heated gilet, heated socks have fine wires running through their fabric to create heated zones, and are powered by small power bank-style batteries secured on the socks themselves.
These ones from BERTSCHAT are designed with hiking in mind, and are made from a soft cotton-acrylic blend. The heated zone runs along the bottom of your foot, over your toes and along to the middle of the top of your foot, providing all-round warmth.
I couldn't feel the fine wires at all while wearing these socks, thanks to the unique way the socks are designed - with the wires on the outer layer of the socks for optimum comfort. The batteries are light and slim, so I barely noticed them during testing. They fit comfortably under my jeans, with the battery pack at mid-calf level - perfect for wearing with ankle boots.
I found the on-sock controls a little unintuitive sometimes. There's just one button to press and hold, three lights to indicate the three heat settings and four smaller lights to show battery level. There's a dinky little remote control included, with a button for each heat setting and an on/off button. A remote means you don't have to stoop down or fish around in your ski boots to adjust the heat settings.
To test the battery performance, I wore the socks on their highest heat setting, using a timer to keep track. I timed 5 hours and 57 minutes of full-blast cosy heat - an impressive performance indeed. The socks can keep going for up to ten hours on lower heat settings, too.
The socks can be handwashed or put in the washing machine on a wool cycle - after removing the batteries and securing the jacks with their attached caps. The fabric felt comfortable and breathable against my skin, rather than sweat-inducing.
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