The MIlwaukee M18 & M12 Rapid Charger accepts all M18 and M12 batteries, providing an upgrade for both systems. REDLINK Intelligence monitors cell voltage, temperature, and charge status to optimize the performance and extend the life of the pack. As an added level of communication, the charger indicates when the battery reaches an 80% charge, providing confidence that a substantial amount of work can be completed without waiting for a full charge. 48591808 48-59-1808