Whether you're working on earning your ticket to Kona, or you already have and are focusing on training for your chance at Hawaiian glory, you know that every second counts in the bike leg. The run and swim are important, but gaining an advantage over every mile on the bike will get you the furthest, which is exactly what Castelli addresses with its aerodynamic T1 Stealth Kona Jersey. The jersey achieves a second skin fit meant to improve your aerodynamics using proprietary Velocity fabric on the front, with breathable Velocity mesh on the back and shoulders. With the combination of these two polyester based fabrics, you get a jersey that will dry rapidly and wick moisture quickly away from your skin as you heat up on your bike, as well shield you from the sun with its UPF 16 rating. The two rear pockets offer easy access to crucial mid race nutrition from your aero bars, and the elastic waist with silicone gripper elastic ensures you won't have to break your aero position to adjust the jersey at all. When you get to T2, leave the jersey on to stay cool on the run or quickly shed it using the Vislon full length zipper.