OptiMate 2 DUO is a battery charger/drip charger automatically adapts to the battery type connected. Guarantees healthy lithium or lead-acid batteries! Automatically charges and provides long-term maintenance. OptiMate 2 DUO makes your battery stronger and lasts longer, no supervision required! For all 12V types of powersport batteries, including lead acid (Pb) > STD (with filler caps), AGM, GEL (sealed VRLA) & EFB and Li-Ion made with LiFePO4 / LFP technology. Safe to stay connected. Warns when battery damage is detected. Energy-saving technology Standby power less than 0.5W. Efficient 24-7 battery maintenance.Weatherproof. Suitable for use down to -40°C / -40°F.