Enrage copied and pasted that exact statement from T-mag.com here is the exact blurb that Tim patterson said...
"*HOT NEW INFO: This is brand-new information that you're going to be extremely excited about: Vitex agnus-castus is a very cool herb that has some extraordinary attributes. Not only does it stimulate the testicles to produce Testosterone, but it, get this, blocks estrogen! It's the real deal, too, not just speculation.
There's ample scientific literature that proves Vitex agnus-castus is a very potent Testosterone secretagogue and it binds (blocks) at the estrogen receptor without causing transcription. The other cool thing about Vitex is that it has a long half-life for an herb. So you only have to take it once a day."......
I have been taking Vitex, but I have also been taking the new Trbiex, so I can`t say what the exact results are, if you want more info on Vitex go to the T-mag forum and do a search on Vitex.