This compound has been around since the late s and is used to treat infertility. It basically helps women get pregnant by stimulating ovulation but it is Clenbuterol used for men who Clen hypogonadism. There is a whole process involved in the body that gets pretty complex but it basically tells your balls to start working on their own again. Nolvadex aka Tomoxifen is also a SERM that has been around forever and was created as breast cancer medication. This compound basically helps keep estrogen rebounds at bay once you come off cycle.