Bontrager's B3 Hooded Long Sleeve Baselayer is a midweight undershirt for cool to cold conditions. The thermal knit material retains warmth, breathes well and facilitates moisture transfer better than a jersey alone. The torso is cut longer so you can tuck it into your tights, and thumb holes in the sleeves make getting additional layers and getting gloves on easy. The close fit, 4-way stretch and smooth exterior give you perfect layering without bulk. And, the low-profile hood easily fits under a helmet and gives you coverage all the way up to your chin and the side of your face.