China ,Extract Source : Latin name is Urtica Diodica and English name is sting nettle .Specification is 95% tested by HPLC.3,4-Divanillyltetrahydrofuran primarily works by attaching to the sex hormone-binding globulin (SHBG). What SHBG does is bind to your sex hormones; mostly testosterone and estradiol. So the basic function of SHBG is to regulate the amount of biologically active hormones in your body. The reasons for this are unclear, however I'm guessing it is because your body loves equilibrium. Anyways, now that we know what SHBG is we can understand how 3,4-Divanillytetrahydrofuran works.Nettle root extract is useding making bodybuilding muscle supplement to make human body perfect.