This is simply the fastest jacket ever made. It's essentially waterproof in the worst conditions. It's as aero as a road speed suit. And it's highly breathable -- you won't be looking to take it off as soon as the rain stops. This jacket can be used in all conditions, rain or dry. It has no insulation whatsoever so for colder days you should add an extra layer. The lower portion of the sleeves fit very close to body to maximize aerodynamics. We couldn't make it fast and easy to put on, so we chose to compromise the ease of putting it on while riding. This will be the jacket that you start with, or if you have to put it on during the race we recommend you make a quick stop. For easy on-off please consider the short sleeve Gabba R. You can delay removing this jacket because you remain fully aero and will not overheat like a normal jacket. It can be removed while riding, but we recommend you practice this and remove gloves prior to peeling the jacket off. The external membrane is somewhat delicate so take care when storing or removing the jacket.