OptiMate 6 Select GOLD series: 9-step 12V 6A sealed battery saving charger & maintainer. The ‘PRO choice’ battery charger that gets the full potential out of your high performance 12V battery. Includes stable power support for tuning / troubleshooting. Ideal for 12V starter (SLI) and deep cycle lead-acid batteries. Select charge voltage of 14.4V for most batteries or 14.7V for premium AGM batteries, or select Power Supply support mode. Selection remains in memory even if AC power is lost. Power Supply mode provides constant power for vehicle tuning, diagnostics and troubleshooting. Fully automatic multi-step program brings the battery safely to full charge. Connect to the battery and OptiMate 6 Select does the rest, no supervision required! AMPMATIC: Automatically adjusts current to match battery size and condition. Temperature compensation: Voltage is adjusted higher when colder, or lower when hotter. Safe to leave connected. Full electronic protection. 24/7 Maintains battery at full charge and good health. Saves your ‘dead’ battery from as low as 0.5V. S.O.H.: Tests battery state of health. Green Technology: 50% less energy, 50% lower cost, Power Factor Correction and Synchronous Rectification. IP54: Weatherproof. Rated for use down to -40°C / -40°F.