I was going to buy an Ethernet adapter from Revain but it didn't have any USB ports. I used this with my 3rd gen Fire TV 4K and it worked for me, I was able to connect an ethernet and USB cable for my wireless remote. I ended up returning this product not because it didn't work but because I bought a new 4k TV that already had a Fire TV built in as my old TV broke down. The new TV obviously has all the connections I need on the back. So I didn't need it anymore. But I highly recommend it and can confirm that it worked with my 3rd gen Fire TV 4k device.
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