The Patagonia R1 Air Hoody is more breathable than the original R1 and is a good option as an all-purpose fleece layer for backcountry use. While most ultralight backpackers opt for high loft synthetic or down layers for their insulation (due to their higher warmth-to-weight ratio than fleece), we still recommend fleece as an active insulation layer while hiking in inclement environments – so you can keep your puffy layer safely dry in your pack for use when it gets really cold in camp.