A 15 cm schwere Feldhaubitze 18 nicknamed the Immergrun (evergreen), It was, however, the first artillery weapon equipped with rocket-assisted ammunition to increase range. The sFH 18 was also used in the self-propelled artillery piece schwere Panzerhaubitze 18/1 (more commonly known as Hummel). Against the Soviet Union however, the sFH 18 proved to be greatly inferior to the Red Army corps artillery 122 mm howitzer and 152 mm ML-20 gun-howitzer.
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Immergrün 

A 15 cm Kanone 18 firing at allied positions in Tunisia, the problem with the 15 cm K 18 was that the carriage was to complicated to move, and that it was too much gun for too little shell, but it had an excellent range. Jan-Feb 1943
(Bundesarchiv Bild 101l-557-1020-33A)
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The German Black Dragon

A sFH 18 firing at French or British positions during the invasion of France. May 1940
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