Upgrade File Caution China distributiion firmware is different by each models customer code. Therefore, its recommend to check Customer code before upgrading firmware. Upgrade Code : /BEBE, /BEBN, /BEEE : SB00B (CSEL = Low) /BSBN : SH00B (CSEL = High) - What is CSEL It means that Its realization state of Slim Drive for notebook. If you use Low product for CSEL, you should use firmware for supporting low. How to check Buyer Code : When you upgrade your firmware, please check the Buyer on your label of drive. If you upgrade wrong firmware, you will have a problem in operating. ex) SN-M242C/ (=Buyer) Please refer to the attached file How to upgrade firmware.