> For the complete documentation index, see [llms.txt](https://www.boxhero.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.boxhero.io/docs/resources/guides/zebra-zd421t.md).

# ZEBRA ZD421T

***

{% hint style="success" %}
Complete the **printer** **setup** and **print** **configuration** in order.
{% endhint %}

## I. Printer Setup

{% stepper %}
{% step %}
If you purchased the **Bluetooth or Wi-Fi module** for mobile printing, open the cap on the bottom of the printer and install the module.\
(Skip this step if you do not have a module.)

<figure><img src="/files/aKwp2ck9mTQWPqkgrZ8C" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}
Pull the **yellow buttons** on both sides of the printer to open the cover.

<figure><img src="/files/shvLai015gGjHBAF2opn" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}
Place the ribbon with the **outer side facing down** and attach it to the holder.

<figure><img src="/files/gkYEtmnvbvYieE5nxGaf" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}
Install the attached **ribbon** into the printer.

<figure><img src="/files/vAG5FlTTw1nSxF7LXqyy" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}
Install the **ribbon core** into the printer.

<figure><img src="/files/Tsp2XTcK1ke9iYHf7u6D" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}
After securing the ribbon with tape, lightly wind it to ensure it lays flat.

<figure><img src="/files/vAG5FlTTw1nSxF7LXqyy" alt=""><figcaption></figcaption></figure>

{% embed url="<https://customer-0jrbilsa8yt3k758.cloudflarestream.com/ec6af04a388a4dcc865bb7b0965c84bd/iframe?autoplay=true&controls=false&letterboxColor=transparent&loop=true&muted=true&poster=https://customer-0jrbilsa8yt3k758.cloudflarestream.com/ec6af04a388a4dcc865bb7b0965c84bd/thumbnails/thumbnail.jpg?height=1080&preload=true>" %}

{% endstep %}

{% step %}
Place the **label** **paper** between the media holders.

<figure><img src="/files/czJ1twg13mnxWlrWNPZn" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}
Close the printer cover and connect the **power** **cable**.

<figure><img src="/files/W7EOkHJayJMzQ20iUqkV" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}
Press the power button and wait for the status LED to turn green. Then press the **FEED button** to check if the paper comes out properly.

<figure><img src="/files/17Sg4hsMz19f3yVKXRDE" alt=""><figcaption></figcaption></figure>

{% endstep %}
{% endstepper %}

***

## II. Print Configuration

Once printer setup is complete, select your preferred printing method and continue to the next step.

{% content-ref url="/pages/sfVSUjgzmGI4QWDoNYCs" %}
[Desktop Printing](/docs/resources/guides/zebra-zd421t/desktop-printing.md)
{% endcontent-ref %}

{% content-ref url="/pages/sfvpGP25duYunWnJAJca" %}
[Mobile Printing](/docs/resources/guides/zebra-zd421t/mobile-printing.md)
{% endcontent-ref %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://www.boxhero.io/docs/resources/guides/zebra-zd421t.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.