JRSC is jackson racing supercharger. It is the more mild (thusly cheapest) supercharger available for zetecs. you could find one used for the above mentioned price and while it doesnt put down as much power as powerworks or some of the other high end kits it does provide a nice performance boost for a nice price.
"Every time something good happens to me you say it's some kind of madness. Or I'm drunk. Or I ate too much candy."