The Klim Zephyr is a fantastic jacket to be worn as part of a layering system. It’s stretchy fabric ensures a great fit and it stops all wind coming through any jacket I wear. It’s shower proof and packs up really small if you want to store it away. I used to wear EDZ’s which are similar but don’t look anywhere near as good as this off the bike and they aren’t stretchy. I would wholeheartedly recommend this item to anyone wanting to reduce airflow through textiles, or aerated leathers for example without adding any bulk. Genius