Our solid earplugs attenuate (reduce) the most. A pair of sleep plugs reduces about 30-33 dB. For industrial noise the Pro31 and Pro27 are the highest attenuating filters: both class 5.
Please note that it is not possible to block out all sound, not even with a custom hearing protection product as sound also travels through the bone structure of your head for example.
Tags: Db rating, NRR rating for earplugs, Noise Reduction Rating, attenuation