This is an injection-plastic military vehicle model kit.
From the manufacturer:
The latest offering from Dragon represents a stunning 1/35 scale kit of an StuH.42 self-propelled howitzer based on a StuG.III Ausf.F chassis. This kit is cleverly based on Dragon’s highly sought-after StuG.III kits, but it incorporates completely new elements such as a retooled superstructure roof and fighting compartment. The front fenders are also brand new, and they are made from photo-etched metal to give maximum realism. Dragon’s StuG.III family in 1/35 scale was already impressive enough, but the line-up has just gained even more firepower with this fine rendering of a StuH.42 Ausf.F with larger-caliber gun!