ULEFONE TIGER stock rom VERSION 2
ro.build.display.id=S518_GQ3031EH1_D2_ULEFONE_V1.00_20161207
I suggest you to flash it with the next version of SP Flash Tool :
http://www.mediafire.com/file/u3iepolka1ru6vy/SP_Flash_Tool_v5.1628.rar
DO NOT choose "Format All + Download" option !
I STRONGLY RECOMMEND YOU the "Download Only" option.
TWRP at the next link :
http://www.chinaphonearena.com/forum/Thread-ROM-Ulefone-Tiger-TWRP-and-Roms