The main material of the Tundra220 bra contains one-third merino wool. The fabric combines merino wool's temperature-regulating and odor-resistant properties with the faster drying of technical fabricsthese are also recommended for situations where you sweat somewhat heavily, as long as the activity doesnt involve high-impact movement, since the support level is fairly moderate. The fabric performs at its best from autumn through spring, and like other products in the Tundra series, these vests are suitable not only for outdoor adventures but also for active everyday use. - Slim fit - Fabric weight: a comfortable 175 g/m², thinner than heavy winter merino wool garments - Machine washable (optimally with wool detergent; regular detergent is also fine, but do not use bleach or fabric softeners) Like all the merino wool products we sell, this is also a mulesing-free product, meaning the painful mulesing method has not been used in production.