Some of the shoeing vises also came with bolt header attachment that the blacksmith used when making his own bolts.

Additional Photo

I also have one made by the same company but it looks a bit different.  I found a picture on line of an advertisement saying it's from 1896.  I haven't found any other information on this yet. 

H. E. Fuller - aka Harry Edger Fuller, of Winterset Iowa, Patented 1908