This handy adapter has a female 2.1mm barrel jack socket on one end and a male USB-C connector on the other, ideal for powering your Raspberry Pi 4 from a 5V 2.1mm DC power supply.
This adapter will pass whatever voltage you put into the barrel jack end, so when using with a Raspberry Pi you MUST ensure it's a well-regulated 5V power supply. The barrel jack has a centre-positive tip.
You can of course use it for any other device that uses a USB-C connection too! We also stock an angled version if you need to lose your power cables to the side.