The innovative GMAX 40V Lithium-Ion Battery delivers high performance and efficiency among all GreenWorks GMAX tools. A quick charge time of 60 minutes for a 2 AH battery and 120 minutes for a 4 AH battery making the NEW GreenWorks GMAX Series of lawn tools a great option when looking to replace gas powered products. Featuring a simple snap on and off design for ease of use and innovative battery charge level indicator, Lithium-ion batteries offer no negative memory effect, consistent fade free power throughout its entire run cycle and 3 times longer run time than Nicad batteries. From mowing and edging, to trimming and blowing.