battery type: li-ion; voltage: 10.8v; capacity: 4400mah/48wh compatible models: lenovo thinkpad t470 t570 t480 t580 a475 a485 p51s p52s tp25 series replace part numbers: 61+ 01av425 4x50m0881 4x50m08812 01av490 01av491 01av492 sb10k97582 sb10k97583 sb10k97584 sb10k97585 sb10k97597 high recycle life,high energy density and long life battery 12 months warranty. 30 days money back guarantee. 24 x 7 email support.