Considered the German Army s most important armored half-track in WWII, the Sd.Kfz.251 allowed the infantry to keep up with the Heer's fast armored elements. The vehicle came in 4 models and 23 variants, but the Ausf.D was the most produced model. In fact, Ausf.Ds represented nearly 70 percent of Sd.Kfz.251s built during wartime. The type's simplified design was the main contributor to this variant being produced in such substantial numbers, and the Ausf.D was the first of the 251s to have stowage bins built into the sides of the half track.