This is a Lenovo C200 Series 6 Cell Li-Ion Battery. This new rechargeable system battery delivers up to 4.5 hours of system run time. Compatible ThinkPad Models: Lenovo 3000 : C200. IBM part #s: 42T5212, 40y8322. Product Specifications: Rating 10.8 V Capacity: 4.8 Ah / 51.8 Wh Color: Silver Size: 1.99" x 1.10" x 8.13" Cells: 6 Cell Lithium-Ion Time live: 4.5 hours average battery life Condition: Brand New