2008 2.3 Auto - Need help identifying coolant part

:
2008 Mazda 5 & 1990 Mazda Miata
2008 Mazda 5, Automatic, Sport, 170K miles

Hi there, I've searched for this one all day, and clearly I must have the only Mazda 5 with this part (Just kidding, I hope). I apologize I didn't circle the part in the photo, but I am trying to identify:

1. This grey box. It has 2 Coolant lines + a plug attached to it
2. The 2 coolant lines attached to it.


Unknown coolant line by Monk Ratava, on Flickr

Please help. If you can help identify the part, I will post a write up of me replacing the defunct parts. I am very meticulous about following up. Thank you so much.
 
Back