Daystate Blackwolf information

i think this "Titanium firing Valve Stem and a tensioned barrel system" is more of a cost / price point / upsell thing... my thinking is that a 17" barrel just wouldn't need a tension system unless it was a straw like a certain other brand...?
It says that for all the barrels besides they all have a carbon shroud , aren’t they using the shroud to tension?
 
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