Worn by itself during spring and autumn or as a mid layer in winter the zenith thermal jersey is a great 3 season jersey for any british mountain biker a lengthy front zipper allows you to regulate your temperature mesh underarm vents provide a constant flow of cool air zippered chest and rear hip pockets provide plenty of space for a phone and keys an elasticated rear hem with silicone gripper keeps the jersey firmly in place low bulk elastic bound cuffs stay firmly in place but