long story, but I've got a situation where I've got a ball that I need to get a head for. (it's for a clamp holding a small lightweight 12 inch 2nd monitor)

the ball measures 1 inch in diameter.Click image for larger version. 

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it doesn't look like the Oben BD-02 ball comes out of the head, and I can't tell about the terra firma or the Giottos MH 1004, trying to get something cheap that works...