CTEK 12 Volt Battery Chargers are easily distinguished by their black labels. All models are staged automatic switch mode smart battery chargers. The 8 stage models have the ability to analyse a batteries state of charge and before a recondition charge to try to recover an aged battery. If however it isn't successful you can manually select the Recond mode to further charge, desulphate and potentially recover a battery from a discharge below 10 volts.