Protect your core from the cold—these heated vests generate hours of warmth and leave your arms unrestricted. Adjust between three heat settings: high (which lasts for four hours on a full charge), medium (eight) and low (ten). A lightweight nylon shell keeps the wind out and an insulating liner retains heat. You can charge any device that has a USB connection with the vest’s built in USB cord. The cord connects to the vest’s rechargeable battery pack.