Seidio BACY32HTMEC-BK Innocell 3200mAh Extended-Life Battery for HTC ThunderBolt (Black) Adds 0.5cm to your HTC ThunderBolt and comes with a black replacement door to accommodate the larger size of the battery Keeps your phone charged and ready to go, even with heavy phone and data usage Capacity: 3200mAh To obtain the full capacity of your battery, 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. For use with: HTC ThunderBolt Adds 0.5cm to your HTC ThunderBolt and comes with a black replacement door to accommodate the larger size of the battery Keeps your phone charged and ready to go, even with heavy phone and data usage Capacity: 3200mAh To obtain the full capacity of your battery, leave the battery/your phone on the charger for an additional 2-3 hours For use with: HTC ThunderBolt After the charging indicator turns green or the battery status shows full.