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.