Tech Rover Replacement Battery for Toshiba Satellite M640-ST2N03 trade; Max-Life Series 9-Cell [High-Capacity] 100% Compatible - Will not void your original laptop warranty Tech Rover&trade; Quality product with 30-DAY Worry-Free Return Policy Brand New Battery, 6600 - 7800 mAh, Effective Capacity All Tech Rover&trade; branded items carry a 1 year warranty against manufacturer defects. 9-Cell High Throughput Battery *Please note this an extended capacity battery and may protrude slightly from your laptop.