Generic 3500mah Extended Power Battery + Back Cover fit for Samsung Galaxy S2 I9100 (Black) It ships from China. Usually takes 9-15 days for arrival, sometimes, it would be sooner than this deadline. High quality Li-Ion battery Description: Battery is an indispensable power source for a cell phone. Therefore, if the battery runs out of power quickly, it really casts a damp over our phone usage. However, keeping an extra battery enables you to enjoy endless pleasure with your cellphone and this Battery would be your best choice. The battery bears the properties of high capacity and dependable performance. It is durable, reliable and lightweight to carry, so it is worthy of your ordering. It is compatible with Samsung Galaxy S 2 I9100 Features: 2. Best replacement for the original battery with comparable standby and talk time 3. Keep an extra battery on hand for extend standby and talk times 4. Integrated microchip prevents overcharging and lengthens battery life 5. The best replacement spare battery for your phone 6. Our battery is sent out with little or no power, so please charge it for about 4 - 6 hours before using 7. The battery operation time depends on conditions such as: Transmitting power level, Signal (distance between the phone and the base station), Network parameters defined by the operator