Battery Type: Li-ion Capacity: 57 Wh; Cells: 6-cell; Voltage: 10.8V Replacement for: Lenovo ThinkPad 51J0499 57Y4186 45N1001 45N1005 42T4791 42T4755 42T4790 42T4793 42t5263 42T4801 42T4708 42T4797 42T4911 42T4733 42T4763 42T4752 42T4756 42T4765 42T4731 42T4710 Battery Fit Models: Lenovo ThinkPad Edge E40 E50 E420 E425 E520 E525 Laptop Battery 100% New from Manufacturer. Up to 500 recharge cycles over the life of the battery. CE-/FCC-Certified for safety Our Service For You: For 12 months from the date of purchase, If the product fails, we will replace it with a new one