2.0 A hour - 36 W hour battery|REDLINK™ intelligence - provides optimized performance and overload protection using total system communication between tool, battery and charger|Fuel gauge onboard displays remaining runtime for less downtime on the job|Temperature management system - keeps battery in ideal temperature range to provide maximum life|Individual cell monitoring - ensures optimal charge and discharge for maximum life|Versatility - powers more than 40 Milwaukee® M18™ cordless power tools|This battery runs cooler and performs in climates below 0 deg F/-18 deg C|Its compact, lightweight design fits in tight workspaces and reduces user fatigue