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This is the hull for the JN-2 SAB, or self-propelled artillery battery, as it appeared later during production. Because the factories producing it could not get the proper alloys to make the torsion bars required by the original design, it has a different suspension. This version is known by industrial designation Object 112-DZ, after Dmitri Zradnyev, the engineer who made the change. The JN-2 SAB is not yet available as a complete model, but if you are interested, you can build a complete vehicle by putting a pair of JN-1 turrets on it.