Supernatural uses many blends of merino wool and technical fibers in its clothing. These Tundra boxers contain just under half merino wool, a corresponding portion of polyester, and 4% elastane for stretch. The fabric dries faster than pure merino wool and is well-suited for almost year-round usetheres enough merino to help regulate temperature changes, for example during hiking, where you alternate between movement and breaks. The odor-resistant property of merino wool is also part of the package. The Tundra series clothing works just as well for active everyday wear as it does for trips, exercise, and hiking! - Slim fit - Fabric weight: 175 g/m², relatively thin - Wide elastic waistband - Machine washable (preferably with wool detergent, regular detergent is also fine; do not use bleach or fabric softeners) Like all the merino wool products we sell, this one is also mulesing-free, meaning the painful mulesing method is not used in the production process.