24-7-365 smart maintenance! OptiMate 1 DUO delivers precise micro processor controlled charging & long term maintenance! Maintain any 12 volt lead-acid battery, sealed AGM (MF) or GEL, or 12. 8V Lithium battery (LiFePO4). 4-STEP program - STEP1: Low Volt Save (4V). STEP2: Controlled CHARGE. STEP3: OPTIMIZE. STEP4: OptiMate Maintenance.