The Proton LT Hoody features breathable insulation to handle the dynamic needs of mountain activities and is an excellent mid-layer that helps maintain a consistent temperature during a variety of intense activities. Breathable insulation lets excess heat and moisture escape through the combination of breathable fabrics and insulation. In addition to being extremely breathable, the Fortius™ Air 20 outer fabric offers unrivaled strength and durability, having proven to be 60 times stronger than industry standards in abrasion tests. Coreloft™ Compact 80 synthetic insulation placed at body level provides excellent stretch and return properties. The No Slip Zip™ system prevents the main zipper from opening on its own, and the insulated helmet-compatible hood adds extra warmth. Put it on and you forget you're wearing it to fully concentrate on the activity at hand.