They are very cheaply made, and prone to breaking, and they don't last half as long as normal games. Save files become corrupted easily, and they don't work alongside games [for example Pokemon, you cannot migrate Pokemon from other games.]

They work for a small amount of time, usually until the seller has had time to pack up and leave. You can usually tell their countefeit by the stickers or colour of the cart. The boxes almost always come flat packed, too.

I got a counterfiet version of Pokemon Fire Red, and found I couldn't migrate Pokemon from it, therefore it's a fake. The seller did refund my money though. Just please, don't buy fakes, they aren't worth it.

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