SAS part question

[Sollord]

I saw this item on ebay listed as SAS expanders and I'm wondering exactly what it does. The chip on it's is an SAS mux but im not sure wth that means http://pmcs.com/products/storage/sas_sata_muxes/pm8380/

 

[Stanza33]

I wouldn't actually call it a sas expander

And it's probably useless without the box to put it in......

Tho maybe it would work alone...??

eg one of these
http://www.sekaimon.com/i221227645146

Looks more like an 2 x SFF-8088 external to SFF-8484 internal SAS adapter to me.

eg a glorified version of this
http://www.ebay.com.au/itm/2-Port-Mini-SAS-4x-SFF-8088-26-Pin-to-4i-SFF-8087-36-Pin-Adapter-RAID-Card-/181284670385?pt=US_Drive_Cables_dapters&hash=item2a35688bb1

.

 

[Sollord]

Looks more like an 2 x SFF-8088 external to SFF-8484 internal SAS adapter to me.

That is what I originally thought but there is only one SFF-8484 inside so I was a little confused on why you'd need 8 incoming sas unless it's a daisy-chan setup