# Send a voice message

This method lets you deliver a voice message to a PSTN number, and deliver voice message to multiple PSTN numbers.

### Arguments

> <mark style="color:green;">to</mark>   The destination to be called. The destination should be a regular number. A regular number should be specified with the country code followed by the number.
>
> Example 2348020000000
>
> You can deliver voice message to multiple numbers at once by adding all the numbers in a square bracket. For example, if you want to deliver to two numbers, specify them in the <mark style="color:red;">to</mark> field:
>
> \["2348020000000", "2348030000000"]
>
> Note: The maximum number of unique destinations accepted in the "to" field is 1000.
>
> <mark style="color:green;">media\_url</mark>   The location of the media/audio file. This specifies where the media file is located.&#x20;
>
> Example  <https://www.learningcontainer.com/wp-content/uploads/2020/02/Kalimba.mp3>
>
> The media file will be fetched and then converted to the most suitable format for the best audio quality over the GSM network.

Example POST request

```json
{
    "to": ["2348020000000", "2348030000000"],
    "media_url": "https://www.learningcontainer.com/wp-content/uploads/2020/02/Kalimba.mp3"
}
```

Specifying <mark style="color:orange;">from</mark> is not necessary as your registered caller id will be fetched and used. If there are multiple caller ids, then only one will be randomly selected.

### Callbacks

For every attempt to deliver a voice message, 9bits sends a status update to your URL configured as a callback.