This style of device-- with the crown "speared" BETWEEN and not ABOVE the crossed swords-- is specific to awards of the Prussian Crown Order with Swords. Since that Order was almost never awarded in its medal bar grades (3rd and 4th Classes) during the World War, it will only normally be found indicating a decoration from a pre-1914 colonial campaign.
It will be found almost always with one of Imperial Germany's three colonial campaign medals-- though there WERE several conflicts for which combat Orders were bestowed without any such campaign medal entitelement.
It is not at all common, both because of the low numbers awarded in colonial wars and because most dealers apparently had insufficient demand for it to stock this device. Very often normal crossed swords will be found on an "Iron Cross" ribbon to represent either the Red Eagle Order or the Crown Order with swords. In odd cases, the wartime Hohenzollern House Order can be found without its normal crown over the crossed swords.
So it is important to "read" what the other awards are on a ribbon bar to deteremine what PLAIN swords on an "Iron Cross" ribbon mean.
This device was more commonly found on the full sized "Old Style" rhomboid ribbon bars in use into 1915.