Our newest Radiator sweater fleece takes performance and style to the next level. Soft, tightly knit polyester offers excellent warmth without bulk or weight, and the clean lines create a more polished look than standard fleece. The mock neck and snap placket provide added warmth and quick venting. Sizing: Back Body Length (in): Medium = 28 1/2 | Large = 29 1/4 | X-Large = 30 | XX-Large = 30 3/4