300 RealFleece™ Descender
Shop NowUsed it for the Arrowhead 135 on Bike (-20 deg F)
"26 hours. It was my base layer under a LS thermal jersey and lightweight down vest (or light puffy when I became cold). I was also wearing a hydration pack. Sweating was controlled the entire time. I loved the thumb holes for when I put the jersey over it so that the shirt didn't bunch up . Very comfortable."

