The Fieldsheer 7.4volt Hi-Vis Heated Jacket is a real work jacket that meets ANSI standards. Hi-Vis is suited for the worker or anyone who works outside or in cold work environments that require a high visual jacket. Powered by a rechargeable 7.4volt lithium-ion battery, the Hi-Vis heat zones keep you warm for hours. When it comes to adjusting heat levels, the Hi-Vis is the industry's only jacket that can wirelessly change heat on the fly. The Hi-Vis provides hard-working heat for serious cold. This garment runs small. We recommend you consult our size charts before purchasing and consider sizing up. Fieldsheer Heated & Cooling Apparel. Work and play in year round comfort.