We are trying to figure out what all blue guns we need for holster making to better serve the XD community. Can anyone tell me what guns are the same frame size? How many frame sizes are there? What's the major differences in the XD and XDM? I had a XDM 4.5 bi tone 9mm a while back but no longer own and have nothing to compare to. We received two blue guns in for the XD and XD compact but I know there's a few more we need. Any help would be greatly appreciated. Help us help you.