You want free flowing movement and you want to keep out the rain. You want to move fast without sweating, or being slowed down by heavy kit. You want a close fit that's not restrictive. Well you want a jacket like the Trailblazer Stretch Jacket from rapid action specialists, Montane. The Aquapro Dynamic is a four way stretch fabric that gives you plenty of movement range, but also keeps out the wind and the rain. Liked by fell runners and endurance hikers, as well as those who like to go a little bit slower but enjoy carrying minimal weight.