How do I install NAS driver?

[desertratr]

Mac newbie. I have added a Macbook to my home network. I have a NAS. I found the Mac driver file on Belkin's website and downloaded it. File extension is sit, which is something called Stiffit. Any idea who to expand a file compressed using Stuffit, without having to buy the Stuffit file expander?

 

[MarkMS]

There is a free version, I believe.

Check this out: http://my.smithmicro.com/mac/stuffitexpander/index.html