In order for us to have keys, we need a battle gear network.
Unlike maximum tune or initial d, our cards are updated through the memory data that are stored on the machines. The keys for battle gear however, are updated via the internet, hence the battle gear network. I think save data occurs on the keys, but to modify your car, it must be done through the network. So even if we had keys, we can't modify cars, so we just accumilate points on and on and on.
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