Anyway I needed to find out more info than was on the bit of paper that came with it. So I googled "Ritmo Quiro External 3.5 Hard Drive enclosure".
One of the pages gave me this:
Ritmo QUIRO 3.5" IDE/SATA USB 2.0 ENCLOSUREPlug & Play 4 faggots?
* Compatible with both USB 2.0 and USB 1.1
* 2 colour indicator
* Screwless, easy to install
* Plug & Play 4 faggots
* Stylish Aluminium cover and stand
* Support Win98/98se/ME/NT/2000/XP/2003/VISTA, MAC OS 8.6/9 and above.
Sheesh go easy - even Linux has plug & play these days.
Some one should grab the /. nerd who wrote that web page by his security lanyard and have a quiet word in his shell like.