Seidio Innocell 3500mAh Extended Life Battery for Palm Treo Pro - Black Adds minimal amount of thickness and comes with a black replacement door to accommodate the larger size of the battery 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: Palm Treo Pro Made from the highest quality Japanese cells Comes with a door in black with Seidio's signature soft touch coating Adds only 3-4mm to your device Keeps your phone charged and ready to go, even with heavy phone and data usage