Compaq Presario A900 SUPERIOR GRADE Tech Rover Brand 6-Cell Laptop Battery 100% Compatible - Will not void your original laptop warranty Tech Rover&trade; Quality product with 30-DAY Worry-Free Return Policy Brand New Battery, 4400 - 5200 mAh, Effective Capacity All Tech Rover&trade; branded items carry a 1 year warranty against manufacturer defects. 6-Cell [Standard-Capacity] High Throughput Battery