The Milwaukee M12™ Heated AXIS™ Vest (M300B-20M) is designed for lightweight durability, fast heat-up, and all-day comfort in cold jobsite or outdoor environments. Powered by M12™ REDLITHIUM™ Battery Technology, it features carbon fiber heating elements that distribute heat across the chest and back. The Quick-Heat function reaches optimal temperature 3X faster than previous models and competitors. Built with AXIS™ Ripstop polyester, this vest is wind- and water-resistant, compressible, and abrasion-resistant—ideal as an outer shell or mid-layer.