Necklace Pendant and Keychain 5g Protection

Pendant size(L x W x H):14*40.4*14mm,Chain size (main chain + extension of the chain): 17.71+ 1.96 (inch)/ 450 + 50 (mm) Cylinder Material: Glass Protection: 5g Shield EMF/EMR Keychain Cylinder: size(L x W x H):14*40.4*14mm EMF/EMR reduces the effects of electromagnetic radiation emitted by data-transmitting electronics, such as cell phone, cordless phones, wireless earpieces, wireless headsets, computers, laptops, monitors, smart TVs, baby monitors, Wi-Fi routers & more Protection Material: Copper Protection: Copper, usually in the form of dust particles will shield against most wavelength radio frequency radiation and other EMF radiation.