These are known as the BMW-type outlet or Powerlet or Hella, Merit, etc. The accessory plugs and outlets meet the ISO 4165:2001 standard and you can find the female outlet with fuse for at little as ...

To circumvent this problem, Apple simultaneously released a new $9 dongle that has female connectors for both Lightning and USB-C, and lets you use the original Pencil with the new iPad.

The connectors are these ancient DIN things, and I don't know what type of adapter I need to use them. Also, documentation on this thing is sparse online, can't seem to find any manuals.