Artillery Luger with "9" grips

i have some photos of "red 9" in a german book. they all are looking like this one and are all done very well. the reason why some lugers (i only know DWM-lugers) were branded (so it's told here in germany) is, because the gun-smithes thought DWM means "Deutsche Waffenfabriken Mauser", but the order to brand a red 9 was given only for the "Mauser" (C 96).