Sonoma County premium mountain biking apparel company Kitsbow recently teamed up with Polartec, a leading innovator of performance textiles, to create a technologically advanced warm-weather riding or running tee. The result, the Radiator Tee, utilizes two innovative Polartec fabrics: PowderDry, a Poly/Lycra blend that looks and feels like cotton, helping to keep you cool and comfy; and, on the side panels, Delta, a new, highly-breathable wicking fabric that reduces skin cling and regulates drying.

Aside from being technologically advanced, the Radiator Tee also has a racy inset design that keeps you looking sharp, an unfettered cut that won’t get in the way, and a dropped tail that keeps you covered where it counts when you’re bent over the handlebars. Added niceties: great ventilation panels start at the pits and continue down the entire length, lightweight, durability, and a subtle touch of reflective ink. Comes in Blaze, Tropic Blue, Citron. Sizes XS to XXL. $69.

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Watch a video about the Radiator Tee here.