When you're chasing dawn patrol pow or tackling high-altitude adventures where the sun reflects mercilessly off snow and rock, the Mountain Hardwear Crater Lake Heavyweight Half Zip delivers the protection and versatility serious outdoor athletes demand. This women's outdoor top combines UPF 50+ broad spectrum sun protection with grid fleece backing that keeps you warm during those crisp morning starts, while the half-zip design lets you regulate temperature as the day heats up or your effort level intensifies. The plant-derived HeiQ Mint anti-odor technology means you'll stay fresh through multi-day backcountry missions, and the thoughtful construction works equally well as a standalone piece for shoulder season hiking or as a breathable baselayer under your shell for winter camping and alpine climbing. Whether you're skinning up for first tracks, grinding out miles on exposed ridges, or layering up for ice climbing, this heavyweight half zip adapts to your adventure while keeping harmful UV rays at bay.