Al-Sulami flag, which was historically used by the Al Bin Ali tribe, and from which the current flags of Bahrain and Qatar originated.

Wikipedia page

It also spawned an old Kuwaiti flag in use until 1871:

https://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Flag_of_Kuwait_Al-Sulami_1746-1871.svg/1920px-Flag_of_Kuwait_Al-Sulami_1746-1871.svg.png

Admittedly, the sources seem a bit scarce on the posted version of the flag. But at least there seem to have existed at least a similar flag used by the Al Bin Ali tribe.