This charger makes use of an inverter type power source which is more efficient then old transformer type chargers and much lighter too.  This compact unit not only does an excellent job of charging but also includes a means to evaluate the battery condition.  The digital display shows charge amperage along with a number of codes that can tell you if the battery has internal short, open cell or sulfated plates and more.  If the battery shows sulfated plates this unit will run a 24 hour battery conditioning cycle to remove it.