Hi Muriel,
Have you got a picture of the part you can share, or at the least a description of what is for/what it looks like?
ELEGOO produces quite a lot of kits, each containing many parts, so without any further information I doubt anyone will be able to help you.
Fabio
Muriel,
That is a breadboard power supply. It plugs into a standard breadboard and straddles the power rails. It can be configured to provide 3.3V or 5V at each rail. It is powered by either USB or the DC barrel jack. There are many manufacturers that have similar versions of this. Here is a link to one on Amazon: https://www.amazon.com/JBtek-Breadboard-Supply-Arduino-Solderless/dp/B010UJFVTU/ref=sr_1_6?s=electronics&ie=UTF8&qid=1547947771&sr=1-6&keywords=breadboard+power+supply.
Ralph
Looks like something that is part of their Starter kits:
https://www.elegoo.com/product/elegoo-uno-project-super-starter-kit/
They do have a Contact option as well.
