Lenovo L20M4P75 L20D4P75 Laptop Battery for ThinkPad P1 ThinkPad X1 Extreme 4th 5th Gen Series SB11B79215 SB11B79216 5B11B79217 5B11B79218 SM11E25311 SM11E25312 5M11E25313 5M11E25314 4 Cell Laptop Battery