DR. BATTERY Professional Series Replacement Notebook Battery: Dr. Battery Professional Series battery is made of quality materials, top grade battery cells to bring your laptop back to life and maintain your laptop service time. Safety First Criteria: All of Dr. Battery Professional Series batteries have short circuit, overheat, and overload protections to maintain the safety of usage. Condition: New Cell Type: Lithium-Ion Device Voltage: 11.1V Capacity: 4400mAh / 48Wh Warranty: 1 Year Compatible Models and Original Battery Part Number: EliteBook 8440p, EliteBook 6930p, ProBook 6450b, ProBook 6550b, TD06, TD09 ** In prevent from purchasing incorrect battery, please compare with your original battery & check the Compatibility at [Specs] below.