Throughout the seasonswe use seasonal weight blended merino wool for great warmth and stretch without bulk making these arm warmers a good choice for everything from mild winter temps to year round early mornings tubular weaving creates a seamless construction allowing them to be form fitting without a fuss and without chafing from stitches or seams constructionanti microbial jersey fabricsmart seams help alleviate pressure points when worn under a helmetreflective brim detail elastic rear p