> For the complete documentation index, see [llms.txt](https://help.verkada.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.verkada.com/access-control/configuration/unlock-a-door-from-a-3rd-party-intercom-system-or-button.md).

# Unlock from 3rd-Party Intercom or Button

You can hook up devices, such as intercoms and buttons, into the AUX cassette of any of Verkada’s [access controllers](https://docs.verkada.com/docs/access-controllers-series-overview.pdf) and all associated unlock events are then logged in [Verkada Command](/command/getting-started/get-started-with-verkada-command.md).

All Verkada access controllers have 2 AUX inputs, located in the middle terminal block, as shown below:

<div align="left" data-with-frame="true"><figure><img src="/files/YoCUIx2tA8cOFUBjawmX" alt=""><figcaption></figcaption></figure></div>

***

## Configuration

{% stepper %}
{% step %}
**Wire the Normally Open (NO) output of the external system to the first input of your access controller, using the IN1 input, as shown in the example:**

<div align="left" data-with-frame="true"><figure><img src="/files/Sqnmw7UZU3nOBVIQWyqG" alt=""><figcaption></figcaption></figure></div>
{% endstep %}

{% step %}
**In Verkada Command, go to All Products > Devices.**
{% endstep %}

{% step %}
**Select the access controller you want to configure.**
{% endstep %}

{% step %}
**At the top right, click Add and select AUX Input.**
{% endstep %}

{% step %}
**Follow the setup flow to configure the AUX input.**

1. Confirm the Settings and click **Next**.
2. When you’re finished, click **Done.**
   {% endstep %}

{% step %}
**To the right of the AUX input, click Delete to remove it.**

<div align="left" data-with-frame="true"><figure><img src="/files/oZacfmA77KSQtwsI2M7a" alt="" width="563"><figcaption></figcaption></figure></div>
{% endstep %}
{% endstepper %}

***

{% hint style="info" %}
**Prefer to see it in action?** Check out the [video tutorial](https://www.youtube.com/watch?v=5MqymenWMdw).
{% endhint %}


---

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