A universal-fit, battery-powered garment just makes sense sometimes for its versatility, and Mobile Warming’s Smart BT Thawdaddy is just that. The light, low-profile design is powered by lithium-Ion batteries that can provide fast heat for up to nine hours, for almost any outdoor activity, including motorcycling. Use it as an underlay to your jacket, or as an overlay to your shirt, and when you’re done, the ultra-thin design means you can stow it away easily. Download the free MW Connect app to pair the vest to your phone, so you can adjust the vest’s temperature or check battery levels. Choose from four heat settings to vary the level of warmth.