Kevin, The frog looks OK to me and looks like late issue for the German Army. The R.B. Nr. (sometimes seen as an R.F. Nr.) indicates a Reichsbetriebsnummer which is factory designator assigned to makers of some items like leather frogs, Luftwaffe drop knives, and other items during the later days of the Third Reich (circa 1943 and later). From the images not mint unissued, but still a very decent example of an issue combat item. FP