Features and Benefits:Charges a 40V max XGT® 2.5Ah battery in only 28 minutes;Charges a 40V max XGT® 4.0Ah battery in only 45 minutes;The XGT® Rapid Charger with dual-fan design circulates air through the battery to cool the battery and circuit board quickly for faster charging;The XGT® Rapid Charger�s digital display indicates battery charge level (-80%, +80%, 100%);The XGT® Rapid Charger�s built-in chip thoroughly communicates during the charging process to control current, voltage, and temperature for more efficient charging;The digital communication within XGT® actively monitors and protects against overload, over-discharge and overheating;The XGT® Rapid Optimum Charger offers key advantages for Makita 40V max XGT cordless tool users. The exclusive dual fan design cools the battery (sold separately) by circulating air through the battery during the charging process for faster charging. The charger communicates with the battery's built-in chip throughout the charging process to optimize battery life by actively controlling current, voltage and temperature. The result is category-leading battery charge times, which means the battery spends more time working and less time sitting on the charger.