Toshiba LITHIUM ION BATTERY PK (8 CELL) ( PA3431U-1BRS ) High quality replacement Lithium-Ion laptop battery rated at 4400 mAh Laptop battery is made using the highest quality cells available and utilize all of the proper logic boards thermal protectors thermistors and circuit breakers to ensure the highest levels of battery safety reliability and efficiency. Replacement rechargeable battery for you to keep as an extra power source handy. This Replacement Battery is 100% compatible with the original laptop battery.