[MX] Change Alpha setting using AS?

Is there a way to change Alpha settings on MC using AS? Something like this:

onClipEvent (mouseDown) {
    ALPHA SETTINGS HERE ( Ex: Alpha=20%)

Im trying to duplicate the window effect on this weeks site of the week: http://www.ijorgeantonio.com

Thanks for the help!

this._alpha = 20;

Thanks Kax!

no problem. :wink: