Dr. Battery Advanced Pro Series Laptop / Notebook Battery Replacement for Acer Aspire 7740-5691 (4400mAh / 48Wh) 800+ Charge Cycles. 2 Year Warranty Type: 11.1 Volt Li-ion Advanced Pro Series Laptop Battery; Capacity: 4400mAh / 48Wh Condition: New 60-Day Money Back Guarantee. 2 Year Warranty Battery utilizes high quality Samsung SDI cells for higher performance longer life and more reliability and it guarentees to meet and/or exceed OEM specification Fast charging. Low power consumption. Built-in protection circuit ensures both safety and stability. This battery only compatible with 10.8V and 11.1V version.Not compatible with Aspire 8930 Series models.