Coolgo New Laptop Battery for HP EliteBook 8530p 8530w 8540p 8730p 8730w 8740w 6545b HSTNN-LB60 HSTNN-OB60 HSTNN-XB60 KU533AA - 18 Months Warranty [Li-ion 8-Cell 5200mAh 14.4V] 8 Cells 14.4V 5200mAh black for HP 458274-421 484788-001 493976-001 501114-001 HSTNN-LB60 EliteBook 8530p 8530w 8540p 8540w 8730p 8730w 8740w ProBook 6545b. Quality Certication: All the products pass the ISO9001, CE and ROHS, FCC multiple international authentication and completely accord with environmental protection requirement. Consummate Design: Excellent design makes the product not only has the overcharge, discharge and short circuit multiple protection, but also to balance charge-discharge of all the internal cells. Environmental Test: Standard modern assembly line. All products have passed a variety of charge-discharge and aging test before they leave the factory. 100% quality test for all items. Operation time: For standard battery(6-cell, 4400mah): 2-3 hours; for extended battery(12-cell, 8800mah): over 4 hours (Note: The actual operation time depends on how much electricity is required by the device and how you use the battery.)