that's just what you see. a fixture with a reflector in it. like culp says, you'll need a bulb and ballast.
i have one of those over one of my tanks though, and i like it.
the lumanmax 3 from sunlight supply is a little better and only $20 more (look for it the same page your looking at the reef optics pendant). the reef optics 3 is an older model. still works fine but the lumanmax is more advanced. either way you'll need to buy a sunlight supply 250w galaxy ballast ($130) if you dont want to do any wiring (those pendants come already wired with cords and male sockets that plug right into all sunlight supply ballast). then you'll also need to buy a bulb of your choice. the total cost is going to be around $350. you can probably find a complete 250w pendant and ballast kit from hamilton (reefstar) or aqua medic(ocean light) for a little cheaper ($300) but they'll have far inferior reflectors (still more than capable on a 29g tall). I went all sunlight supply when I had a larger tank and couldn't have been happier with their products.