ok, I'm going to admit it. I am really confused about this whole topic. First question, esp. in regards to the above posted statement about the ease of one type of STP device, that it works through the zipper. I understand that part, but then how does it pass?? I mean doesn't any device need to look like a penis? I mean, guys "whip it out" and pee. And if you're using something that does not pass, what if another guy enters the men's room when you're "busy". I know these sound like stupid questions, but this is new to me, and I do want to understand. And I will have to make these decisions soon, Right now if I ordered a STP or packer, I'd be in big trouble at my house.