This dock does exactly what I expected it to do.
I connected this to my mains charger and my iPhone 3gs sits perfectly in it.
This should also have an auxiliary in, which means you can plug your headphone in or a speaker.
I have connected my alarm clock to it and it works just like an all in one dock type thing.
The only problem is that when you go to your music, whilst the phone is in the dock, you cannot change the volume of the music on the iPhone. So if you had headphones in the auxiliary then you would not be able to change the volume - just bear that in mind.
But I use the auxiliary for speakers so I have no issues with the volume.