Specifications: Specifications (DC18RD 2-Slot Charger) – Charging time: Two 1.8 Ah/18 V Li-ion batteries – 25 minutes, two 3.0 Ah/18 V LXT Li-ion batteries – 30 minutes, two LXT Li-ion batteries 4.0 Ah/18 V – 40 minutes, LXT 5.0 Ah/18 V lithium-ion batteries – 45 minutes. Specifications (BL1850 Battery): Charge indicator capacity: 5.0 Ah, battery voltage: 18 V. The dual-port Li-ion charger charges two batteries simultaneously. During the charging process, the built-in fan cools the battery by pushing air through the ventilation slots, allowing for faster charging. The charger communicates with the built-in battery chip during the charging process, optimizing battery life through active control of current, voltage, and temperature. The charger features a built-in USB port for charging portable electronic devices.