These are assembly line leftovers. Evidently if the vehicle was going to get a CD6 radio, this is the block that was installed and the special face insert that comes with the block was snapped in place as well. We've been told you can upgrade a single CD radio to this CD6 by simply swapping blocks and replacing the trim piece in your face. However, there might be more to it than that since they offer different sound systems that are not interchangeable. So we are selling these for exact replacement only.
We have several crates of these. That's why the price is far cheaper than you would normally find for an OEM Mazda CD6 radio block. They are new, in un-opened boxes at the moment, although we open each box to inspect the contents and apply our warranty seals.