Breaking from the standard review, this video demonstration had my full interest and now, endorsement. {Spoiler Alert} The DIRITIUM Level III +PS Plate shown in the video is dropped, stepped on, then beat with a hammer, and then a hand axe. Calling that a good start, the same plate is then shot over 35 times, with some well known calibers from the AK, the AR15, 300 Blackout, .357 Sig, and 12 Gage Shotgun. Zero penetrations. Granted, I wouldn't want to absorb the kinetic force behind these impacts, but I've honestly never seen anything close. [NOTE:Yes, I did, but we're not counting Batman movies.] Having one of these in my kids backpack would offer a life-saving opportunity.
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Absolutely Amazing
There is a good variety of products there, different degrees of protection offset by size/weight/and cost.
Realistic uses include: you and your child's backpacks.. or using a standard vest/plate carrier when you're in a firearms class.. or you shoot someplace free - from oversight by a Range Safety Officer. This seriously falls into the category of 'better to have an not need, then need and not have'.