Milwaukee Battery Pack 18V 4.0A LI-ION – M18 B4:

Delivers up to 2x more run time, up to 20% more power and up to 2x more battery life compared with other Lithium-Ion technologies and/or with previous MILWAUKEE® battery technology (Results depend on tool and application)

REDLITHIUM™ protection with REDLINK™ digital overload protection to prevent users from damaging their cordless power tool investment in abusive situations

Individual cell monitoring ensures optimal charge and discharges for maximum life

Durable metal frame battery construction with shock responsive separators preventing pack failure from excessive vibrations or drops

Water protection routes water away from the electronics & out of the battery pack

Can be used in extreme temperatures down to -20 °C without compromising on runtime and battery life

On-board battery fuel gauge helps the user to maximize his battery run-time efficiency