Very nice Karl, and shows very clearly what I noticed from a cutaway drawing, the triplock crown has 4 O-rings not 3, I think the real plus for that crown tube is the two O-rings on the inside not just the one on the outside that people instantly recognise.
Did Randall notice the crystal on the ZEX, I remember the discussion before on whether it was a armoured acrylic or not?
regards
siggy