Hole in Konami Famicom carts?

[Tupin]

I know Nintendo wasn't really strict with case designs for the Famicom in Japan, but I was wondering what this hole in Konami carts were for. They look like something that you would loop something through, almost as if they sold them in vending machines loose/put them in those claw machines.

Any ideas?

[Gapporin]

So you can make a Famicom keychain/necklace out of them! Duh!

To be honest, I don't know, but I have noticed the hole on my Gradius 2 cartridge. The vending machine idea sounds plausible, though.

[JC]

The most likely reason is that it helps to better clamp together the front and back of the cart. I've never opened one, so it might also help hold the board in place.

[tubeway]

It's so you can loop a wrist strap through it, like a cell phone.