This made me laugh because when I was a kid living in Europe, my dad would often travel to the US and bring back unreleased in Europe and/or NES games from the US because they were much cheaper. To get them to work with PAL/Secam NES, we took our NES to this (shady?) electronics shop that installed this silver mechanical switch. You would insert the US cartridge and if memory serves, the screen would blink and when the image was on, you flipped this switch and the blinking would stop, permitting you to play the US cartridge in the European console. That was my 'Nintendo Switch'