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# init(sessionID:data:)

Initializes a transport message for a specific feature.

```
init(sessionID: UUID, data: Data)
```

## Parameters

`sessionID`

A unique identifier for the feature that the message belongs to, such as notifications or Live Activities. The value is fixed while the accessory remains paired through AccessorySetupKit.

`data`

The message data to send.

## Discussion

Create transport messages when your accessory sends data back to the data provider through [`sendMessageToDataProvider(_:)`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/sendMessageToDataProvider(_:)).

---

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