Decibullz top rated DIY Thermo-fit Molded Earpieces combined with professional acoustic filter technology. Decibullz Custom Molded Professional Filters provide a tuned and flat attenuation. This reduces all frequencies by approximately the same level so everything sounds like it is supposed to sound without damaging the users hearing.
This is a product that I was totally unfamiliar with but seemed like a really good idea. Growing up in the age of classic rock, I listened to a lot of music at levels that were no doubt damaging to my hearing. Working in the steel mill also had serious noise levels. This was in a time period where ear plugs were not recognized for hearing protection or at least not used.