Hot Chilly 's Micro-Elite Zip-T - Men 's: Hot Chillys (R) Men 's MEXT Mountain-Weight Zip-T is one of the warmest body fit base layers that is fleece on the inside and has that 'jersey ' look on the outside. It is heavy enough to wear as base layer or as an everyday sportswear second layer. The fabric is smooth and soft outside with plush, ultra-low loft fleece inside; made with moisture transfer fibers that pull moisture away from the body to keep you comfortable in extreme conditions. Hot Chilly's Micro-Elite Zip-T | Men's | Black | Size Medium