Schumacher SECF-12V-OBD Automotive Computer Memory Saver
If you are tired of resetting your clock, radio presets, remote car starters, etc., every time you unhook your battery, then this cable is exactly what you need. Simply plug the OBD plug into the vehicle that you wish to unhook the battery on, and then plug the Cigarette Lighter End into a Power Pak, then change your battery.
3 foot long cable assembly
Plugs an external power source into the vehicle's OBDII port
Preserves the stored fault codes and programmed electronic settings,
such as clocks, radios, seat positions, keyless entry systems, alarms, etc.
Lightweight and easily transportable