Hcg is a hormone that women secrete when they are pregnant, and Hcg is made by prego women who volenteer to pee in a cup and donate to hcg companies, they separate the urine from the hcg and make it into the powder protien form. Hcg mimic LH therefore ur testis absorb it and produce testosterone and goes into spermogenisis. The sperm makes ur balls grow again. Use it while ON or the weeks waiting for pct and thru pct but only 4-5weeks max u can desenstize ur nutsack if u go over bored. Clomid was originaly made for women who wanted to get prego, it so happens in a man it makes produce more test by interrupting the negative feedback loop, it cobers all estrogen receptors and makes the body belive there is no more estrogen and men make estrodoil from testosterone by aromatase enzyme. So ur pituritary produces LH and FSH that goes to ur testis and makes testosterone take arimidex to not allow excess estrodoil to be produce.