This is the bottled version of Alpha Pharma's enanthate: a 10 ml vial at 250 mg/ml, two and a half grams of hormone behind one rubber seal. Testosterone enanthate has been manufactured since the 1950s and remains one of the most widely produced injectable esters anywhere.
Like every testosterone preparation it converts in part to estradiol through the aromatase enzyme, which is the reason aromatase inhibitors are usually catalogued next to it. The oil solution is given intramuscularly and, because of the long ester, acts as a slow depot rather than a fast-acting injection.
