For survivalists and explorers whose lives depend on their equipment, having a knife with a broad tang is important.
This makes it hard to break, but it adds weight and still provides only a single, large blade.
Today’s invention is a knife which has a large tang in which a slot is cut (so that it doesn’t lessen the strength of the unit significantly).
Into the slot is inserted from the far side a multi-tool penknife, one grip of which is expanded to provide the handle for the overall system.
If you need access to a wider range of smaller tools, simply undo the two knurled nuts holding the small tool and grip (blue) in place and detach the main metal work from the penknife/multitool.