Yes, the "10" mark, or 1/10 of a cc/ml. The same amount of GH drawn in the same insulin syringe would be approximately one-half a cc/ml, so it's good to double check. If you reverse the two, in confusion you would inject 50iu's insulin.....lights out!
Are you going to use 10iu right off, for the first time? If so, you might want to start at 4 or 5iu and work up, just to see how you react to humulin-r. If you don't get the carbs right for 4 hours after injecting, you will get a hypoglcemic reaction that can be a bit unsettling. It's happened to me a couple of times in awkward places.........nothing like running for sugar to stuff down while visiting "straights".
So how have you been kk? You are no novice to this stuff, are you? Hey, send me a mail sometime with the news.