I have the MSA Sordin Supreme's which are good ear defenders, although one annoying issue is the battery cover has an extra "mushroom" looking piece of metal on the end ,which prevents the ear defenders from collapsing in on themselves for storage without wearing out the rubber shroud or distorting the frame. Unless I'm missing something it's a really silly oversight IMO. I presume it's so you can tether it to the main unit, but they forgot to provide the tether! A jewellers saw fixed mine!
One question about electronic ear defenders - Do they simply amplify non damaging noise or do they actually cancel out the harmful audible range? i.e. Are they any better at shielding your ears from loud gun fire, than non electronic ear defenders or are they just good at allowing ambient sounds around you? Does that make sense?
Features: Compresses harmful noise to 82dB. Amplifies safe noise x 4 times