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 Polymer Device Voltage: 7.5V Capacity: 4100mAh / 31Wh Warranty: 1 Year Compatible Laptop Model: Transformer Book Flip: TP550LA TP550LA-BH71T-CB TP550LD TP550LJ Compatible Original Battery Part Number: 0B200-00860200 C21N1333 C21NI333 ** In prevent from purchasing incorrect battery, please compare with your original battery & check the Compatibility at [Specs] below.