ViFly ToothStor - 4 Port 2S Balance Charger with Storage ModeVIFLY ToothStor is a combination of 2S charger and discharger. It has 4 target voltages per cell (3. 8V 3. 85V 4. 2V 4. 35V), set your target voltage like 3. 8V cell (LiPo Storage Voltage), it will start the charging or discharging process automatically when the battery is lower or higher than 3. 8V. Check out our other Chargers and all of our ViFly Products! Features: 4 Port 2S Balance Charger with Storage ModeYou can balance charge four 2S batteries