What Our Gearhead(R) Experts Are Saying:"I wore the Lightweight Sleeveless Base Layer under a summer jersey, and it kept sweat moving away from my skin the whole ride, even during a hot afternoon climb."Hot rides call for a layer that disappears, and the Rapha Lightweight Sleeveless Base Layer does exactly that. Worn close to the skin under a summer jersey, it wicks sweat away and regulates temperature so the heat of the ride never turns into chafing or discomfort.