Halo25 was first introduced during the 1960's-70's olympics, during this time the East German Team utilised this compound on its original name Turinabol to dominate the competition. Halodrol is a 17aa steroid that converts to the steroid oral Turinabol after interaction with 3b-HSD at an estimated rate of about 5%.
Because of this low conversion, doses must be higher than other 17aa pro-steroids. However, it is suspected that Halodrol has decent potency without conversion as good results are seen despite the relatively low conversion to Turinabol. Based on Vida’s data Halodrol appears to be about as potent as testosterone, and significantly less androgenic.