...11-oxo is also a precursor to a very effective muscle building hormone known as 11-ketotestosterone. 11-ketotestosterone is some amazing stuff; not only does it not convert to DHT or estrogens, but it also has the lowest intrinsic estrogenic activity of any natural steroid hormone. The myotrophic boost you get from the 11-ketotestosterone will keep your muscle mass intact during your cutting phase, which will not only make you look better but will also enhance your fat loss through the maintanence of a high metabolic rate.