Arclyte's Sony laptop battery is designed to be 100% compatible with your Sony laptop with part number(s)VGP-BPS9/S; VGP-BPS9A/S. Our laptop batteries use only premium lithium Li-ion and Li-Polymer cells which offer quality, longevity, and safety. This battery is guaranteed to fit properly and will meet the performance standards of the original. If you are not satisfied, contact your reseller within 30 days to send the battery back for a refund. For more information please visit Arclyte.com.