The base of the Tiger's turret becomes visible when you lift the turret off. If a model Tiger has an interior, you might lift the turret in order to display it. This model from Ustar has an interior, but its turret base is incorrect.
The real turret was fixed to the hull by bolts, threaded through the hull roof from underneath. All of the bolts would be removed to detach the turret. The turret base would then match this CAD model. The walls and the base ring are flat and level. There is a narrow gap, a rubber seal and the bolt holes.
But Ustar have put a trench in their turret base, and in the trench they have bolt heads. As well as being incorrect, this suggests that Ustar used Rye Field's model kits as a reference, because Rye Field made the same error some years prior.
This defect is very difficult to correct.