4.0 Ah 56 Volt Lithium Ion Battery Industrys first 56VÂ battery40% More Power Compared to the leading 40V BatteryPatent Pending Keep Cool Technology Keeps each battery cell cool for extended lifePatent Pending Power Management System Protects the battery from harsh elementsIntegrated Fuel Gauge Shows how much power is left in the batteryFast Charge Time Charges in 30 minutes with the 30 Minute Charger80 Minute charge time with Standard charger30 Minute charge time with 30 Minute chargerCompatible with all EGO Power Power Equipment