The late Thomas Jentz looks at the development and employment of the massive German Karl-Gerät super-heavy self-propelled mortars. Wartime photographs taken by the manufacturers, PK units and after eventual capture by the US and Soviet forces show the details of the huge SP guns.

The author has collected 74 photographs of the mortars, their ‘Munitionsschlepper’ supply vehicles and the twin-bogie rail cars used to transport the mortars by rail. There are no scale plans in this book, although there are 18 wartime illustrations.