Samsung SM-G531M Stock Firmware (Flash File) The Flash File will help you Upgrade, Downgrade, or re-install the Stock Firmware (OS) on your Mobile Device. In addition, the Flash File (ROM) also enables you to repair the Mobile device if facing any Software Issue, Bootloop Issue, IMEI Issue, or Dead Issue. File Name: G531MUBU1AOFB_G531MUUB1AOFB_v5.1.1_4File.zip Country: Panama File Size: 762 MB Android Version: 5.1.1 Flash Tool: Odin Download Tool How to Flash (install): Follow Tutorial (Mediafire)