Allstart 561 Intelli-Clamp LED's on clamp will flash to let user know of trouble with either unit or vehicle. Number of flashes determine trouble code that can be referenced Cross Polarity Protection - If the user hooks them up backwards, you have no spark. Red LED on clamp will et you know they are still not active Short Circuit Protection - If the vehicle has a short in the battery circuit, the clamps will automatically shut down Real Time Amerage - The Clamps recognize cranking amps in real time, cranking time is set accordingly to protect the unit and vehicle, Auto-Shutoff - Once the vehicle is started, the clamps will automatically shut down Designed for use with Lithium Ion Jump starters.