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We understand that you are inquiring if the latest Roku Express is compatible with an Ethernet adapter.
Please be advised that Not all Roku devices support using an Ethernet adapter to connect to your wired network. To help determine if your device is compatible, you need to know the device model. To find this information, go to the home screen on your Roku device and select Settings > System > About.
The models below support an external third-party Ethernet adapter.
For full information on this, you can take a look at this link: How to use USB to connect your Roku streaming device to a wired network | Official Roku Support
We hope that we have addressed your question appropriately, but reply to this message if you have other questions and concerns, and we will gladly follow up.