# What’s the counterbore and countersink?

_Published: 2016-03-26_

Somebody may not know the different between counterbore and countersink on PCB.

Both are used to mount nails to keep the PCB in the suitble position.

The cross-section of the counterbore looks like letter “T”, but the countersink looks like a funnel.

Pls see the below picture:

![PCB counterbore](https://www.bestpcbs.com/blogimages/2016/counterbore.jpg)PCB counterbore

![PCB countersink](https://www.bestpcbs.com/blogimages/2016/countersink.jpg)PCB countersink

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