If you're talking about what I think you're talking about... It'd probably be one of these:
They're great at getting the undercoat out if you have a good one, but a lot of the really cheap ones are just worthless. (Fingers could do a better job of brushing the dog out. lol.)
How long is your boy's coat? It's hard to tell by the pictures I've seen on him, but you could use a dematting rake on him, probably. They're a little harder to use (and find!) but they are AWESOME for taking out the undercoat.
I get all of my grooming supplies from Ryan's pet supply, since there is a warehouse near Phoenix. (I really just want excuses to go there -- it's like a candy store for me. Tons of dog stuff that is SO cheap.)
I'd think most of these would work for brushing out the undercoat:
http://www.ryanspet.com/ryanspet/category.asp?categoryCode=208&
PS - I have heard great things about the Coat King when used on thick coated breeds, but I've never personally used it.
ETA - It (the coat king thingy) is more or less what Zoom posted.