Just to clear up a little confusion about hearing protection.
Hearing protection devices have what's called an NRR rating. That's how much noise they soak up. Anything over what they soak up gets to your ears.
If a pair of muffs have an NRR of 33 and the noise you're exposed to is 140 dB then the muffs soak up 33 dB of the 140 dB. This leaves 110 dB to get through to your ears. Add plugs to the muffs and you get anohter 5 dB protection added to the higher of the two. NRR 30 plugs + NRR 20 muffs = NRR 35 combined. NRR 30 plugs + NRR 30 muffs still equals NRR 35 due to the different frequencies the muffs and plugs absorb.
For electronic muffs the same is true. The advantage electronic ear muffs provide is that there's a microphone on the outside and a speaker on the inside of the ear cup and the speaker shuts off when a shot is fired and is on when the sound level is normal. The muffs still have an NRR rating, but it's only applied when the noise has a fast rise time, like a gun shot or a hammer on a nail, because the electronic circuitry shuts the speaker in the ear cup off when the shot occurs. This means that the NRR rating is for the muff when they're off or when the circuit turns off the speaker.
None of them absorb all the noise over 85 dB.