Complex sentence: It used the same chassis, superstructure, engine and transmission as the U- 34 and was armed with a new 122 mm M-30S howitzer designed by F. F. Pietrow's design bureau.
Split into simpler sentences: It used the same chassis, superstructure, engine and transmission as the U- 34. It was armed with a new 122 mm M-30S howitzer designed by F. F. Pietrow's design bureau.