Schumacher"s Instant Power Battery features a built-in high pressure air compressor and a built-in charger for automatic charging of internal battery - just connect an extension cord to the plug to recharge (cord not included). Also features a USB Port, 12 Volt accessory outlet with overload and short circuit protection, an on/off switch that activates the jump starting and USB modes, charging and charged LEDs to indicate charging of internal battery, and battery status LEDs to tell when battery is charged or needs to be charged. Sure grip clamps fit both top and side mount batteries, and cables stay flexible in cold weather. Maintenance-free, sealed, lead-acid battery allows storage in any position, with compact, durable and corrosion proof polypropylene case.