Product review (2 stars): Do Not Use Use For Dust Collection
I bought this duct work for my air collection system in my workshop.  It's clear, 4", and long enough.  And the price is great!  Right?  Wrong.  Yes it's clear 4" flexible duct work, but it's not that rigid.  In fact it's so flexible that my Jet 2hp dust collector will actually cause it to collapse in on itself and create a vacuum.  Thick of what happens when you suck up a plastic grocery bag in the vacuum cleaner.  It's sort of like that.

That being said, just because it didn't work for my system, doesn't mean it won't work for yours.  I'm sure there are uses for it, just not in workshop dust collection.  Therefore, 2 out of 5 stars.  negative 2 because it's flimsy and another negative because the clamp broke.