Features: 1) Built-in far infrared heated fiber cloth 2) Built-in store heating material. Features:1) Built-in far infrared heated fiber cloth2) Built-in storing heating material.3) It can be used on the stadium,campaing,fishing,hunting,and anywhere you like. It is no need the battery.4>It is only 0.8kg,can be take any where easy.5>12V, using car cigarette lighter as the charger, charging around ...