Provides optimized performance and overload protection using total system communication between tool?? battery and charger</br>Best-in-class construction: Offers long-lasting performance and durability</br>Fuel gauge on board: Displays remaining run time for less downtime on the job</br>All-weather performance: Delivers fade free power in extreme job site conditions</br>Add any M18 Tool-Only Option to Build Your Own Kit</br></br>Product Description</br></br>Delivers up to 2.5X more run-time?? 20% more power and 2X more life than  standard lithium-ion batteries. The M18 REDLITHIUM XC 5.0 Extended  Capacity Battery Pack features superior pack construction?? electronics??  and performance to deliver more work per charge and more work over the  life of the pack than any battery on the mar