Arcteryx have designed a really versatile fleece jacket that layers easily under waterproofs and is light, but essentially warm. Made from Polartec's Classic 100 Micro fleece with a small grid velour finish to the outer fabric that dries quick and packs down small too. Arcteryx work hard to design the fit of their garments to move as the body moves during activity. Articulation in the sleeves on the Delta LT stop the sleeves riding up and gussets on the under arm help with extended reaching when climbing or scrambling, plus the Delta's slim fit means it stays close to the body and is more efficient under shell jackets. The Delta LT comes with two zipped hand pockets and a laminated, zipped sleeve pocket for smaller items.