The ultimate pocket tester for on-vehicle performance & alternator voltage testing with either 12V lead-acid or 12.8V LiFePO4 starter battery - easy troubleshooting from cranking to charging Checks battery voltage to provide an indication of battery health; checks battery starting power and checks charging system without disassembly by indicating low charging voltage As easy as 1-2-3, connect to battery, check state of charge, start engine tester displays cranking voltage and vehicle charge simultaneously - 15 seconds is all you need Includes two cable straps, adhesive hook-and-loop straps and screws for use if mounting the removable backplate into an enclosure Display cranking volts down to 6V and charge voltage range up to 15V - check weak battery or overcharging Easy to use! Connect with the included clips to the battery or connect to an installed SAE battery lead Battery clips are removable and replaceable. TESTER CRANK / ALT TS-121