The Jöttnar Uller Yak Wool Base Layer’s name is arguably slightly deceptive, it’s actually made from a blend of Tibetan yak wool and polyester, but whatever the fine details, the end result is one of the best – if not the best – winter weight base layer tops we’ve ever used.
For starters, the thick, winter-weight, fabric is amazingly soft and luxuriously comfortable against the skin. It is genuinely a pleasure to pull it on, a bit like sliding under a warm duvet on a cold, winter’s night.
Meanwhile the cut is sleek and close but not tight, helped by a little bit of stretch in the fabric. It’s decently long too with a bit of a drop to the tail, which helps avoid cold spots at the base of the back due to the top rising up.