Got it about a month ago for $160 only used it to show her how. Compact, portable device will test your alternator to make sure it is in proper working order and delivers serious jump-starting power with 1400 peak amps and 700 instant starting amps. That's enough power to jump-start a 12 volt AGM, GEL, and WET battery in your car, truck, SUV, motorcycle, boat, RV, ATV, or tractor; connect the clamps to the battery, turn on the switch and start vehicle. The reverse polarity alarm will alert when theres improper connection. A high power LED light and LCD screen readout with real time information helps you work in the dark. Jump starter equipped with digital 120 PSI air compressor with auto stop and Surefit nozzle. Built-in USB ports to charge phone and electronic devices.