ChristThePhone
Fractal Fanatic
It does say, "CE certified to BS EN 352-2-2002 - SNR35." I'm guessing SNR35 means 35 dB isolation..?
Anyway, it looks like all it is is a foam ear plug with a piece of metal you stick into it lol.
https://elacin.com/blog/elacin-wiki/what-does-en352-2-mean/
SNR stand for Simplified Noise Level Reduction Rating