This is a shiny, new couscoussier. There were traditional copper or even earthenware ones. Then there were aluminium ones. Now they're stainless steel.
BUT remember that a colander over a saucepan of water works just as well. Asking around, it seems most households just use this method. One less gadget in the cupboard.
Here's a small amount I'm steaming. (Yes folks, my 1959 Frigidaire De Luxe stove - vintage to the end).
NOTE: Don't go all holier-than-thou health food, wholemeal couscous. It's not nice. Doesn't absorb the butter or the sauces well.