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The NRR is 23 decibels (dB)
You can charge the case using the supplied charging cable.
Comparing the two is honestly a laundry list beyond how they look. Obviously one is wired and one is wireless, but they function in very similar ways. The AXIL however, does clip sounds over 85dB, where the E-Max Shadows do not. Beyond that, the AXIL Ghost Strike Extreme also provides a higher NRR than the Shadows, as well as a longer operating time on a single charge. The Shadows do come in with the advantage of the case serving as a charger for the earplugs. You can check out some more on the AXIL's here: https://www.opticsplanet.com/axil-ghost-stryke-extreme-earphones.html
These have a 23dB noise reduction rating.
There is not a safety cord, but it does come with multiple ear tips to achieve a more custom fit for each user.
These have an internal battery with an estimated battery life of 5 hours per charge. It includes a case that can recharge the earplugs 4-5 times, so you can get approximately +20 hours of use from the earplugs and case.
These have a 23dB noise reduction rating.