Your old t shirt with the cut off sleeves just won't get the job done when the temperature is pushing 100 and the pavement is radiating heat, but Mavic's Cosmic Pro Men's Cycling Jersey will. Made primarily from 37. 5 fabric, a polyester that's been designed to instantly attract and wick moisture, the Cosmic Pro is your best bet on the hottest, most tire melting days of summer. It uses a specially knit wicking matrix to transport vapor up to five times faster than standard polyester, and has lightweight side and shoulder panels and a mesh back for increased breathability and comfort. It covers all the standard jersey basics, too. Three rear pockets hold all the small items you want to keep close, the full length front zipper provides plenty of ventilation, and UPF protection helps save your skin when you're riding under a baking sun. There's even a media port to route headphones and snug bands at the sleeves for a slim, aerodynamic fit that won't flap or slip.