A USB-C to Ethernet adapter is what lets you take a phone, tablet or modern laptop off Wi-Fi and put it on a wired connection. Hardwiring is the step that actually removes the radio from the equation, rather than shielding around it, which is why this sits next to the Cat7 shielded cable on the shopping list.
What to look for: gigabit (1000 Mbps) rather than 10/100, a braided or shielded lead, and a chipset your operating system supports without a driver download. Any of the mainstream gigabit adapters do this job; there is no EMF-specific version and you should not pay a premium for one.
Once wired, turn Wi-Fi off on the device. Leaving it on means both radios stay active and you get none of the benefit.
