user1499: Can we find out about the parts that the arduino uses?
I want to make a shield, and i bought the same power jacks.
And i thought that there would be two pins, one for power, one for GND.
However, it has three pins.
The supplier did not have a datasheet, and right now i do not have a continuity beeper either, so could i see its datasheet somewhere, or does anyone know why it has three pins?

user69592: This is an image from a typical power jack:

The specific ones you bought may differ.  The vendor should be able to supply you with a manufacturer and P/N or an actual data sheet.
Image copied from: https://www.we-online.de/katalog/datasheet/6941xx301002.pdf

1499: <p>Can we find out about the parts that the arduino uses?</p>
<p>I want to make a shield, and i bought the same power jacks.</p>
<p>And i thought that there would be two pins, one for power, one for GND.
However, it has three pins.</p>
<p>The supplier did not have a datasheet, and right now i do not have a continuity beeper either, so could i see its datasheet somewhere, or does anyone know why it has three pins?</p>
 69592: <p>This is an image from a typical power jack:</p>
<p><a href="https://i.stack.imgur.com/MBQAz.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MBQAz.png" alt="From here https://www.we-online.de/katalog/datasheet/6941xx301002.pdf" /></a></p>
<p>The specific ones you bought may differ.  The vendor should be able to supply you with a manufacturer and P/N or an actual data sheet.</p>
<p>Image copied from: <a href="https://www.we-online.de/katalog/datasheet/6941xx301002.pdf" rel="nofollow noreferrer">https://www.we-online.de/katalog/datasheet/6941xx301002.pdf</a></p>
