Acase 2800 mAh Extended Battery for Motorola Droid 2 with Replacement Cover (Black) Made from high-quality Lithium Polymer cells. Comes with a black case featuring Acase soft touch coating Double of the original battery life. Keeps your phone charged and ready to go, even with heavy phone and data usage Capacity: 2800 mAh In order to obtain the full capacity of your Acase battery, we highly recommend that you leave the battery/your phone on the charger for an additional 2-3 hours after the charging indicator turns green or the battery status shows full Adds only 0.9cm to your device