I was able to find one source stating that 17-pro is 1,4-OHP or 17beta-(1-ketoethyl)-androsta-1, 4-diene-3one, 17a-ol. There seems to be a couple of different claims as to it's target conversion hormone. The most believable based on the structure is that it is a boldenone precursor. If that is correct, I wonder if it has a higher conversion rate than 1,4 DHEA (boldione).