The M12™ Power Source, compatible with all M12™ Battery Packs, features a 2.1 amp powered USB port that charges tablets, smart phones, mp3 players, and other portable electronic devices. This smart-charge port identifies the electronic device being charged; delivering fast, safe charging. The adapter features an on-board fuel guage, and is compatible with all M12™ Heated Gear, providing up to 6 hours of continuous heat on a single charge. (Battery sold separately).