This is a TimeGuard security light timer, designed for use with standard indoor bayonet-fitting pendant lamps. Can be used with old-fashioned filament bulbs (max 100W) or modern energy-saving bulbs (max 20W). It will do either random intervals during darkness, or turn on at dusk and turn off at a specific time.
It's fully working, with instructions, but note that it needs reasonably high ambient light levels to work (it won't work in a heavily shaded room). Note also that the instructions to programme it are a bit hard to follow - but it does work once you've got to grips with that!