Lightweight Fleece:
Lightweight fleece is the most versatile fleece, bridging the gap between heavy base layer and mid layer insulation, with the benefits of both. Active outdoor athletes who generate lots of body heat choose this fleece for its low bulk, breathability, and stretchy form-fit under trim softshells. You’ll find lightweight fleece perfect as a light mid layer for high output pursuits like cross-country skiing, as extra-heavy base layer in arctic conditions, or over a tee like a sweater in autumn.

Midweight Fleece:
Practically ubiquitous, midweight fleece is everywhere, and is what comes to mind when most people think of fleece. Midweight fleece is warm but not heavy, and makes a great outer layer when it’s chilly but not rainy, windy, or below freezing. As insulation over wicking base layer, most midweight fleeces disperse moisture well, and should function adequately under a waterproof breathable shell for everything but sub-zero temps or cold weather endeavors that don’t involve a lot of activity.

Heavyweight Fleece:
Traditional heavyweight fleece has been shoved out of the spotlight by newer, high-loft synthetic insulation and windproof fleece, but it’s still a great alternative to both when weight and wind aren’t a concern. While heavyweight fleece can be bulky, it resists abrasion, insulates well, remains breathable under a shell, and has permanent, warmth-trapping loft no matter how wet it gets. Wear this type of fleece for low-to-medium output activities like belaying or hiking in cold, damp environments.