Innovative technology with no internal battery so no need to wait hours for the unit to charge before use, simple & safe to use with no long term battery storage issues. This power start can be fully energised in Approx. 2 minutes. If the vehicle battery is faulty or is holding less than 5 volts the Electro Start 800 can be pre-charged via another vehicle's battery or the 12V accessory lead. Compact & lightweight for easy handling & storage, yet still delivers the same result as heavy, bulky, lead acid battery equivalents, making it ideal for the professional mechanic & DIY users.