I'm laughing because I just posted all that I have and we're on the same course! I have split 3 5mg Zep pens into a vial! It is super easy. You don't need to do anything fancy. I bought 4ml sterile self healing vials, 4ml for the larger surface area. I alcohol swabbed the top of the vial. I unlocked the pen, centered it on the vial, pressed the injection button, held still, and whoosh, all in there. Did it with 2 more pens and because I was going to use it within a couple of weeks, didn't add BAC, no loss, no fuss.