A SMART CHARGER CHARGES DRAINS CHARGES DRIANS AND THEN CHARGES THE BATTERY IN A CYCLE TO DETERMINE ALL ITS PARAMETERS AND EVALUATE IT, the ones that for all intents and purposes are new but no longer unused or show signs of installation! BECAUSE THE BATTERY WILL SHOW SIGNS OF PREVIOUS INSTALLATION AND HAVE BEEN FITTED THUS INCURRING VARIABLES AS SCRATHES OR MARKS AND AS WE CAN NO LONGER SELL THEM AS "NEW"!