Like ski and cycling clothing, running clothing should be warm and windproof, but elegant and comfortable. The Pearl Izumi Ultra Wind Block Jacket is just the ticket. It is a semi-forming lightweight jacket that resists cold and wind. Paired with the signature Ultra Relaxed Tights (and maybe a second layer on very cold and/or windy days) these have become my go-to winter running gear. And as a bonus, the rust colored jacket is highly visible and very stylish. Excellent purchase.