Are there any tests done by the company to prove your product blocks any signal?

Hello there, Thank you for contacting us. We have had our products tested by an FCC independent lab that specializes in RF/Microwave testing. The lab uses directional measurement in an isolated environment, which eliminates all external influences, ensuring no test result interference. You can see the results on our DefenderShield website under the About section or by copy and pasting the following link on your browser: https://www.defendershield.com/testing/ Warm Regards, The DefenderShield Support Team

How do you wash this hat to keep emf-proofing?

Hello, Thank you for contacting us. We encourage gentle hand washing and hanging to dry as the preferred method of caring for the beanie as continued use with a high level of agitation in a washing machine can potentially break down the silver fiber shielding material. Please rest assured that we are very confident that this would not be the case with just one use. We hope this information helps! Kindest regards, The DefenderShield Support Team

What is the circumference of the medium size beanie please?

Hello there, Thank you for contacting us. The Child Size - EMF Protection Beanie circumference is: 20-25 (inches). The Adult Size - EMF Protection Beanie Circumference is: 23-28 (inches). Hope this answers your question. Warm Regards, The DefenderShield Support Team

The majority of commercial 5g networks are relying on spectrum in the 3.5 ghz range (3.3 ghz-4.2 ghz). does your hats protect from this frequency?

Thank you for contacting the DefenderShield Team. the EMF Radiation Protection Beanie is designed to shield (5G) RF radiation (300 Hz-10 GHz) from reaching the head, by acting as a barrier between your head and a device or source of emission. we hope this helps.