I have 12V power adapter with 4 pin mini-din connector, but the computer case only allowed barrel connector. This box together with barrel-barrel cable allows to power this pc with the adapter.
parts i have used:
https://www.aliexpress.com/item/32950204848.html
https://www.ebay.com/itm/10x-Male-DC-Power-Plug-Connector-Screw-Female-Panel-Socket-Adapter-5-5x2-1mm-Hot/153521317854
and some m3 screws.
Note in one picture the barrel sockets are soldered wrong, the black wire should be on the other pin. I had to disassemble and resolder.