Optimate 2 battery saving charger-maintainer with low voltage start charges dead-flat batteries from as low as 2 volts 4 step fully automatic program. Perfect for charge and maintenance of all 12v lead-acid std, agm, gel and 12v lifepo4 'lithium'. Safe long term battery care, battery remains at 100 percent whilst optimate protects battery by providing current to all connected circuitry alarm, instrument display etc. Extends battery life up to 400 percent. Hook it up every time you park the vehicle / craft. Continuous low current pulse balances cells and makes battery stronger, last longer. Perfect for away-from-home /on-the-run maintenance - light-weight, weighs only 1pnd / 450grams including ac power cable and charge cable.