The Deltas – warm, efficient, made to move – were created for climbing. Evolution and refinement have led to a versatile design ready for any mountain adventure. A great cold-weather midlayer – or standalone in milder temperatures – the stretchy Polartec Power Dry fleece’s voided grid construction delivers a high warmth to weight ratio and has a smooth face that layers easily under a shell. The ScubaHood fits under a helmet and integrates a panel that wears as a neck gaiter or balaclava.