Our Felix Underwool Half Zip Shirt by Ivanhoe of Sweden is made of 100% extra fine Merino wool. This piece is perfect as a base layer or by itself.
I wore this on my last trans-Atlantic flight and the temperature responsiveness was perfect for a long flight where it can get cold, then hot and stuffy, then cold again. (As an added bonus, I looked great.)
Fabric & Care
100% Extra Fine Merino Wool
Wool is anti-bacterial and odor resistant so you do not need to clean it often. When you do wash, use Wool cycle, then shape and air dry. Like your pets, wool should never be put in the dryer.
Dry Clean if you are fancy.
Ivanhoe is very close to American sizing, so stick with what you usually buy. For the waist sizes, don't freak out! Most companies use vanity sizing, vanity is in short supply in Sweden so they use the actual sizes in inches.