This is an injection-plastic military vehicle model kit.
Desperate to get heavy artillery to the front lines, the Germans during WWII dropped their big guns onto almost anything that would roll. In this case it was the tiny Panzer I chassis that was burdened with hauling a 150mm Howitzer, mounted in a huge box-like superstructure. Very interesting!
Dragon's release of this self-propelled gun is another of their "Smart Kit" releases, providing the most detail for the least hassle. The kit includes ready-to-assemble "Magic Track" indy-link tracks, a modicum of photo-etched metal detail parts, clear parts, a metal gun barrel, and markings for five vehicles. Also includes ammunition.