The Boulder 125 1/4 Zip is a versatile, thermoregulating base layer from Artilect. It\'s designed to offer effortless performance in a modern fit. Using an ultra-lightweight Nuyarn® 125 g/㎡ merino fabric with matching strategically placed eyelets under the arms for increased breathability, there is no better combination of performance, comfort and durability in the world. FeaturesSuperior, bluesign® approved 125 g/㎡ Nuyarn merino technology offers unmatched warmth-to-weight ratio, 5x faster drying and remarkable durabilitySuperfine, mulesing-free, Australian merino wool for maximum softness and comfortIncredibly stretchy and elasticEasy Fit offers a modern fit with full coverageTargeted placement of eyelets for increased breathabilityChafe-free flatlock seamsGusset in the armpitsMachine washableLoop for dryingYKK zipper