The Rapha Pro Team Insulated Gilet uses Octa insulation placed strategically through the body, warm enough for a cold start to a high-tempo training ride without holding onto that heat once the effort builds. A two-way zip dumps heat on demand, and the whole vest packs down small enough to disappear into a jersey pocket once it's no longer needed. Contrast stretch panels move with the body, and an encased back gripper keeps the fit locked in place. What Our Gearhead(R) Experts Are Saying:"I start a hard interval session cold and stay warm through the opening efforts, then crack the zip open the second my heart rate climbs. By the cooldown it's packed into my jersey pocket and I've forgotten it's even there."