Has anyone ever heard of this or know of it's rarity?

Its a device that used back in the day, to log into your bank account using a Famicom, and do all kinds of stuff

I have a chance to get on mint complete wiith box and Manual and the included number pad controller, used to log into bank accounts for $60.

Anyone got any advice on this? I thought I had heard of everything for the Famicom, but this is new to me, so any help would be greatly appreciated.

Thanks so much!!

Yours,
Rob