So you think you know the Northern Ireland flag?
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Ulster Day falls in the last week of September and this year marks the 98th anniversary of the signing of the Ulster Covenant, when hundreds of thousands of unionists swore to oppose Home Rule.
But what would you say if we told you that the flag commonly associated with Northern Ireland, has no official status?
We sent our reporter Conor Macauley to find out more, and see if he could find an alternative.