Innovative patented technology with no internal battery so no need to wait hours for the unit to charge before use. Simple and safe to use with no long term battery storage issues. Can be fully energised in approximately two minutes. If the vehicle battery is faulty or is holding less than 5 volts the E/START800 can be pre-charged via another vehicle's battery, a Micro USB charging cable (not included) or the 12V accessory lead. Digital display indicates battery voltage, capacitor charge and faults. Can also be used as a 0.8A battery maintainer using a USB charging cable or a 2A battery charger with the addition of Model No. E/START2A Charging Adaptor. Compact and lightweight for easy handling and storage, yet still delivers the same result as heavy, bulky, lead acid battery equivalents.