Hipower 6 Cell Laptop Battery For IBM / Lenovo Thinkpad Edge 13, E30, E31, 57Y4565, 42T4813, 42T4815, 42T4806, 42T4807, 42T4858, Battery 73+ Laptop Notebook Computers Cells: 6 Cells Voltage: 10.8V Capacity: 4400mAh; 47Wh