The Ready-HeatTM Vest uses the same heating technology as our blankets, and comes in an Overhead Style for maximum comfort. It warms to 100°F/37.8°C in 8-10 minutes, and works off a low amount of oxygen making it perfect for wearing under your jacket for increased protection against the cold. Our Ready-HeatTM Vests are great for EMS or construction workers in the field. During nighttime or cold weather accidents, EMS workers can spend hours on the side of the road saving lives, our vests will help them remain warm and focused. The vests also have many recreational uses such as hunting, fishing, marathons, hiking or climbing. Any outdoor activity can be made safer, and more enjoyable with our new Ready-HeatTM Vests!