These Saturn on top are two prototypes that were sent from Sega Japan to both, European and USA headquartes in order to decide the final shape of the final model. As it can be seen, the model on the right looks a lot like the final shape that the final model has. The unit on the left however looks more like the original Mega CD2, and the rare Multimega that combined Megadrive-Genesis and Sega Mega CD. As it can be seen in the video (that is linked below) and the pictures, it has big door open button, a defined blue power button and a red led that show the word indicator probably for reading purposes.
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