13B REW Help?

I made couple resin copies of rx7 r1 kit engine. Now i need some advice on identifying couple of parts. I know that 2 is alternator. Is 3 a AC compressor. And under it will be placed power steering pump. But what is that 1?
http://img202.imageshack.us/img202/7607/13bm3kl.th.jpg (http://img202.imageshack.us/my.php?image=13bm3kl.jpg)

The item in question is the coolant/water pump. Hope this helps you out.