I wasn't sure what to expect from these, but I've seen Peltor Optime 105 earmuffs used in many professional settings and wanted to try them. No one has really done this, but I'm actually going to compare them with pretty much the best noise reducing headphones today, the Sony WM-1000XM4. So, what's the difference? -Their noise reducing capabilities are similar, but the WAY noise is reduced is completely different -The Sony headphones are better at reducing both high and low frequencies (for example, you can hear your own voice very well with the Peltor earmuffs, but much less so with the Sony headphones). -"Overall" the Peltor earmuffs feel like they reduce ambient sound a bit more. The Sony headphones retain a very small level of pleasant white noise (I suspect, to mask the limitations of their amplifier etc). It's hardly noticeable, but it's there. -Subjectively, the remaining environmental noise is considerably more pleasant on the Sony headphones. They do a better job of "taking you out of your environment" in a pleasant way. With the Peltor earmuffs, it feels like your head is in a tight jar, which is fine, but it's not as relaxing. -Low frequency sounds like the beating of your heart, movements of your head etc - are much less noticeable with the Sonys, which is a big benefit. Those sounds can get annoying on the Peltor if your environment becomes quieter. -The amount of noise reduction from the Peltor earmuffs depends almost completely on how hard they clamp around your ears, which is why they are extremely tight out of the box. This is not true of the Sonys. Since they rely on electronic noise reduction, they don't need to seal around your ears nearly as much, which makes them a lot more comfortable to wear for a long time. They are also smaller and a little lighter than the Peltor earmuffs. -The electronic noise reduction of the Sonys has conservative upper limits, which means that even a little bit of outside wind will overload their external microphones, and you'll hear all kinds of noises on the inside as a result. The Peltor earmuffs don't have this problem of course, which makes them the only solution for actual extreme noise (jet engines, weapons, heavy machinery etc). In other words, if your goal is ear PROTECTION, then no electronic headphones are going to cut it. -The obvious benefit of the Sony headphones it that you can also play music, get game audio, watch videos and whatever else appeals to you. -The obvious benefit of the Peltor earmuffs is that there is no battery to drain, unlike the Sonys. There is also the cheap price of course. Since a lot of people are using these Peltor Optime 105 earmuffs for conservative personal applications, I wanted to offer this comparison. If they are too tight for you, the metal band can be stretched out a little, but you will lose some performance. In a critical application with deafening sounds, I wouldn't do that. In a personal application, it would be fine.