Made with innovative Intraknit™ technology, the Smartwool Intraknit Thermal Merino Base Layer Colorblock Crew is designed with colorblock patterning for a distinctive look. It is 3D-knit to enhance performance, and it offers mesh zones for better breathability in all the right places. Plus, this crew is built so that it fits as though it’s custom-made just for you. With enhanced durability features such as ribbed elbows, this shirt will last for a long time to come.Details:Fit: Slim Engineered construction uses knit structures to enhance performance with lighter weights and cleaner finish Mesh ventilation seamlessly knit in gender-specific zones designed to keep the body dry and comfortable 3D mapping results in near custom fit and freedom of movement while ribbed elbows provide added durability Avg Weight: 208g (7.34 oz)