Review on EMI RFID Grounding Block Anti Radiation Electromagnetic by Deejay Allard

I bought two of these to use over and under my son's bed to protect him from EMF and WiFi. I tested these sheets by putting my phone underneath and they block calls and wifi. That's how they work. I don't know what level of protection they offer for my specific use, but I'm guessing it's better than nothing. I think it's sensitive to electrical signals, so I'd like to give it a try.