Variant of the jihadist black flag. This particular version is used by the "Islamic State of Iraq" and by al-Shabaab in Somalia. 
It shows the shahada in an arrangement that includes the image of the historical "seal of Muhammad"
(more precisely, the "seal" design is based on a 1980s facsimile of Ottoman era copies of letters written and sealed by Muhammad, in which the copyists had manually inked the seal impression; the jihadist flags seen in press photographs do not show the seal as circular but in a slightly irregular shape that faithfully mimicks one particular such specimen; see w:seal of Muhammad for details).

Also note that the representation of this seal formerly uploaded to commons but since deleted is merely a graphist's  "fictionalisation" of what the seal might have looked like; the actual artefact on exhibit as the "seal of Muhammad" in Istanbul is rectangular)
svg image based on press photographs (original 2007 upload apparently based on a picture of the "Official website of Islamic State of Iraq" which can not now be traced; press photographs showing this flag first appear in early 2006).
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