STROKE TEST, 1. lesson:

Image credit: Unknown, found in the Internet by Google. Take a look of the image above. It shows a brand new tech rig, which represents the top quality technical diving gear, and it's supposed to be very fine rig! Question: What do you think? Is it DIR or not? A: Oh, it's so fine! I envy the guy who has it! B: It's a DIR, yes. C: I'm a little suspicious... D: Stroke!