These still exist, you can buy them on Amazon. [1] I figured these had to exist as I recently saw a device to make a lan using mains circuits. [1]: https://a.c

These still exist, you can buy them on Amazon. [1] I figured these had to exist as I recently saw a device to make a lan using mains circuits. [1]: https://a.co/d/31rKR02 https://a.co/d/31rKR02