HX40 T3 housing question

[xxNocturnalxx]

I'm thinking about going with an HX40 and was looking around for some t3 housings. I noticed some are 4 bolt and some are 6 bolt. What is the main difference? Most of the HX40s I see seem to be 6 bolt but I was looking at these and they are 4 bolt EXTREME PSI : Your #1 Source for In Stock Performance Parts

Am I missing something here?

 

[Cdc1221]

Those are for an h1e if I'm not mistaken, which only use 4 bolts

 

[xxNocturnalxx]

I see, I'm surprised they don't offer a 6 bolt option

 

[Cdc1221]

Very interesting indeed. I'm not sure on that one. I know that the hx35/wh1c housing is 6 bolts, according to this http://www.dsmtuners.com/forums/turbo-system-tech/436168-holset-turbos-part-9-a.html

But that's the Bolton housing. I would contact bep and ask them

 

[JusMX141]

The .55 bolt-on housings have six bolts, the .70 T3 housings have four. It doesn't matter.