Take advantage of more power using 18V XR tools with FLEXVOLT ADVANTAGE technology. A unique electronic module with pack identification technology enables the tool to recognise when an XR FLEXVOLT battery is attached and unlock even more power. The DCD999 delivers up to 42% more power when paired with a DCB546 XR FLEXVOLT 6Ah battery versus a DCB184 18V XR 5Ah battery. Engineered for speed and durability, other features include an all metal 3 speed transmission, DEWALT built brushless motor and full metal ratcheting chuck with carbide inserts.