They are made of something different......what is it??? Designs are always changing but this is a "material"
"I hear bacon sizzling in the pan"
I forgot...yes the decibels level and "time at the high level" not how high breaks those little hairs in your ear. You can still hear but it is rather muffled. The theory with earphones or earplugs is that they block the wave going into your ear so the hairs dont break...you have hundreds of thousands of them. So concerts arent bad without earplugs wont harm your ears because its only a few hours at high levels but for musicians doing it night after night it wrecks havoc on the ears....