A great value thermal jersey that you can layer up with to suit your needs performance is just right in milder conditions where it39s fleece fabric maintains warmth but has excellent of breathability so you don39t get hot and clammy simply combine with differing base layers jackets and vests for multi season adaptability thermo flow fabric a highly breathable thermal fabric that also features a dimpled surface pattern that helps both the aerodynamics and the evaporation of moisture i