The Rheinmetall heavy Infanteriegeschutz 33 was the most powerful German support weapon at the beginning of World War II, and in January 1940, the first attempts were made to transform it to a tracked vehicle. An improved version, based on the Panzer II chassis, served in Rommel's Afrika Korps, and further alterations were made during the battle for Stalingrad in 1942. The Grille Ausf. H, the adaptation of the sIG 33 on the Czech Panzer 38(t) chassis, served from 1943 onwards with the schwere Infanteriegeschutz companies of Panzergrenadier regiments. This book covers a wide range of modelling projects based around this ubiquitous vehicle type.