Duckworth has re-invented this world-famous knit in wool. First created in 1912 by JE Morgan (Long John Morgan) the waffle stitch traps dry air in generous micro-pockets against your skin, creating a buffer that regulates your core comfort. 80% Helle Rambouillet plus 20% Nylon to help maintain the waffle shape. Possibly the world's lightest warmest fabric. Your instincts will tell you when to break it out.
What a great find! I could not be happier with this shirt. I have a hard time finding long underwear that fit but not this time. Plenty of length in the sleeve and body.