Seidio BACY35HTMEC-BK Innocell 3500mAh Extended Life Battery for HTC ThunderBolt - Battery - Retail Packaging &ndash; 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: 3500mAh 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