Yeah, are you asking about measuring the contents you draw into the syringe? Most have markings that are tenths of a ml. So .5ml is 5 divisions, also marked by 1/2ml. But if your asking about gear contents, it depends on what you have. Example, Test Cypionate 250 is 250mg per ml. So .5 ml would be 125mg. If you have primobolan 100, you have 100mg per ml. So .5ml would be 50mg. My noobness is still learning so if any members have more knowledge, please correct if necessary.