If this is for Niall, the instructions sent out specifically said no gifts, but I assume it’s on an artist by artist case.
They check your bags, but as long as the item is not on their forbidden list, you should be ok. You probably should check with the band's manager as well.
I would believe that it should be permissable. They didn't check me, but i also didn't have a backpack or item with me.
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