It is what it is. - Premier Body Armor Vertx Commuter Sling & Gamut 10"x17.5" Level IIIA Bulletproof Backpack Insert

Light weight and stitched properly. Fits the Vortx bag with no problem. It stays tightly in place and behind a pocket. Not much to say because I’m not going to test it. They do sell different sizes for different size bags. It does have tapered edges on the top so it’s not exactly square like most book bags. Best for the vortx as that’s what it’s designed for.