I've had many "bottom end" Lasko's over the years. All basically the same.. rectangular steel box, 2 braces holding the motor (one end only) and a 5 bladed fan. The box owes its rigidity to the two plastic screen grids screwed to the front and back. All seem to have plastic "feet" to help stabilize it front-to-back so it stands better from the force of air being forced through. They typically are all 3 speed.