This is an amazingly versatile jacket. It is a windproof textile jacket for cool days, but fold down the inner windproof panels on the chest and back; open the full length arm vents and side torso vents, and you have maximum air flow on hot days. An additional removable zip out Airguard waterproof liner means you can handle wet weather, and the included removable thermal EverHeat liner keeps you warm when it gets cold. Sas-Tec CE certified viscoelastic armor is used in shoulder s and elbows . From touring in cold wet climates, to commuting in hot humid places, the Yosemite jacket will handle it all.