> For the complete documentation index, see [llms.txt](https://developers.oxylabs.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.oxylabs.io/products/headless-browser/device-type.md).

# Device Type

Instead of manually setting viewports, touch support, and User-Agent headers in your local library config (which can create fingerprint mismatches and trigger connection timeouts), the Headless Browser allows you to emulate specific device classes natively by adding the `p_device` query parameter to your connection string:

```bash
wss://username:password@ubc.oxylabs.io?p_device=mobile
```

### Supported device profiles

You can configure the `p_device` parameter using three supported device profiles:

<table><thead><tr><th width="123">Parameter value</th><th width="620">Description</th></tr></thead><tbody><tr><td><code>desktop</code> <br><em>(default)</em></td><td>Full-size viewport, desktop platform headers, standard mouse/keyboard input schemas, and a desktop User-Agent string.</td></tr><tr><td><code>mobile</code></td><td>Compact mobile viewport, touch event APIs enabled, mobile OS platform headers, and a mobile User-Agent.</td></tr></tbody></table>


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