The M12 Heated AXIS Vest, Nos. M300-21 and F300-21, from Milwaukee Tool, deliver heat built for lightweight durability. Powered by Milwaukee's new Hexon Heat technology, this vest is engineered to stay warmer for longer in all temperatures. With AXIS rip-stop fabric, the vest protects against the elements without sacrificing movement. The compressible, lightweight construction provides warmth whether worn as a mid-layer or durable exterior layer. The hidden battery pass-thru pocket allows for front or back battery placement, increasing versatility depending on the situation. Available in men's and women's sizes.