I used a Kennedy box like that once, during my thankfully brief career as the maintenance guy in a waterbed frame factory (lots of stories, some frightening, about that place). Nice design. You can't put any tools as wide as the inside of the box in, because the tray gets in the way; but mostly this kind of box is used for mechanic's tools (in the broad sense of "mechanic," someone who works on mechanical stuff), which tend more toward long than wide.