"What Our Gearhead® Experts Are Saying: ""I wear the Vigor 1/2-Zip on everything from fall trail runs to winter layering days. It breathes really well but still gives you that touch of warmth when the temp drops. Super comfy, stretchy, and never bulky under a shell."" We reach for the Outdoor Research Vigor 1/2-Zip Pullover when we need that perfect balance of breathability, warmth, and mobility. It’s our go-to midlayer for shoulder-season hikes, backcountry tours, or even chilly morning commutes. Built with OR’s ActiveTemp™ technology, this pullover adapts to our output, keeping us dry and comfortable when we're working hard. The 1/2-zip design adds quick ventilation, while flat-seam construction and stretch fleece fabric give it a movement-friendly fit that never chafes or clings. Whether worn on its own during brisk hikes or layered under a shell in alpine weather, the Vigor 1/2-Zip keeps us cozy, dry, and ready for anything."