What is the correct width of the ribbons on a WWII German ribbon bar?

I am a WWII German reenactor and I would like to make a ribbon bar for the ribbons that I have earned for the events that I have done. I know that there were 2 different sizes of ribbons manufactured and I was wondering if there might have been a third. The typical ribbon issued with the medal was 30mm and the buttonhole ribbons were 25 mm. Would the ribbon bars have been made using the buttonhole ribbons or was there a narrower ribbon for the ribbon bars. I have found a vendor that has the original metal bars that I can make my own ribbon bar with a bit of wool for backing. Any help would be greatly appreciated.