The “parent” thread, in which this discussion started, is in the Rifles/Carbine section. SouthNarc’s breaching hammer, being visible, in his pack, with his SIG Rattler, started the the sidebar discussion, which took on a life of its own.
I bought several of an earlier version of the Stanley FUBAR; one for the home/family, one for my personal vehicle, which I carried with me on patrol, and at least one more, gifted to a colleague, on my patrol shift. The original device is a pry bar, nail puller, hammer, hook, and something I cannot name, but is used to grab a piece of warped lumber, and pull/twist it into place while constructing things, or, grab a piece of lumber, and pull/twist, while destructing things. These are the non-emergency uses that come to mind. The emergency uses would include breaching, and rescue of folks trapped inside structures, in a situation ranging from a weather event or fire, to a mass-homicidal event. Some killers have barricaded doors/windows, and, even if that is not the case, one may need to force entry through a normally-locked door or window, or go right through a wall.
If a home or other structure has been hardened, at the doors and windows, for security, one may elect to create a field-expedient door.
The device, itself, has shifted, somewhat, from my originals. At one point, there were two or three sizes available, if I recall correctly.
One problem, with the tool, itself: The tool, as sold by the BORG (Big Orange Retail Giant) is not only heavy, but its balance makes it unwieldy. It is FAR heavier than a carpenter’s framing hammer. GearFondler’s modifications should help remedy this, though the capability of pulling nails and twisting lumber would be removed. Arguably, one should have an original version, for the home and/or vehicle, while sending another to GearFondler, for conversion to the backpack version.