Testosterone Propionate is best injected every day or every other day due to its metabolic short life thus most people prefer test cypionate as it only needs to be injected once per week. If propionate is the steroid of choice, ancillary drugs such as nolvadex, proviron and arimidex are advised to have on hand during the cycle in case symptoms of gyno arise (or if you wish, you can run these drugs during the cycle for prevention). All testosterones will aromatize, although some have a lesser chance of it. Propionate may be one of those drugs, but proper precautions should be taken, nevertheless. 100mg per ml, 10ml vial =1000mg