Product review (4 stars): Venting good - Doesn't come with clamps for installation...
Product came as stated.  The metal rings it comes with - I have no idea what these are for.  I had metal clamps already, but I feel like it's worth noting that the venting does not come with them to connect/install. The rings supplied - who knows what they are for, but not for installation. Overall, length is good, and product is sturdy and works as you'd expect. I would recommend for the price.