https://www.vice.com/en_us/article/xgzgw4/faraday-cages-for-wi-fi-routers-are-the-latest-5g-conspiracy-grift

If you’re scared of 5G giving you COVID-19 or otherwise polluting your precious bodily fluids, then some companies on Amazon would love to sell you a cage for your router. According to sellers, the metal cages block 5G. According to reviews, they’re destroying people’s Wi-Fi signal,  which makes sense. The metal boxes are just Faraday cages marketed to people who believe in baseless conspiracy theories about 5G. 

The sellers claim the metal cages will “block up to 95% EMF RF waves” and allow you to browse the internet while blocking 5G signals. According to reviews, the cages work and absolutely destroy Wi-Fi signal strength.