Can you imagine a jacket so light, that it nearly disappears when you put it on? Castelli already has. Their Squadra Long jacket is made with a windproof, water-repellent and breathable fabric that's impossibly lightweight. They've even added and expansion vent in back to prevent overheating. It gives a close-to-body fit without binding, so you won't feel constrained. Compact design stuffs into your own pocket for easy transport.