> Fetch clean Markdown by appending `.md` to any page URL under https://signalwire.com/docs or requesting it with the HTTP header `Accept: text/markdown`. The root index at https://signalwire.com/docs/llms.txt lists the available documentation indexes. # StoredDevicePreference > Serializable subset of MediaDeviceInfo for persistence. Serializable subset of MediaDeviceInfo for persistence. The browser's MediaDeviceInfo interface is not serializable. This stores the fields needed for device recovery across sessions. ## **Properties** **`deviceId`** `string` — required The device ID. --- **`groupId`** `string` — required The group ID (identifies the physical device). --- **`kind`** `MediaDeviceKind` — required The device kind. --- **`label`** `string` — required The human-readable label. --- > Serializable subset of MediaDeviceInfo for persistence.