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# addAdditionalDevice

> Adds an additional media input device to the call.

```ts
addAdditionalDevice(options): Promise<void>
```

Adds an additional media input device to the call, as a second capture alongside the main connection. The call itself is unaffected when acquisition fails.

## **Parameters**

**`options`** `MediaOptions` — required

Media constraints for the additional capture. See [`MediaOptions`](/docs/browser-sdk/v4/reference/interfaces/media-options).

---

## **Returns**

`Promise<void>`

## **Throws**

* [`AuxiliaryLegCancelledError`](/docs/browser-sdk/v4/reference/errors/auxiliary-leg-cancelled-error) — [`removeAdditionalDevice`](/docs/browser-sdk/v4/reference/self-participant/remove-additional-device) removed the device before its leg finished connecting.
* [`AuxiliaryLegTimeoutError`](/docs/browser-sdk/v4/reference/errors/auxiliary-leg-timeout-error) — the leg did not connect within its budget.
* The raw `getUserMedia` error (e.g. a `NotAllowedError` `DOMException` on permission denial) — inspect `error.name` to decide how to react.

## **Examples**

```ts
await selfParticipant.addAdditionalDevice(options);
```

> Adds an additional media input device to the call.