Good Quality, check the length
Your review: Tough to find non-insulated duct. This fit the bill. Shipped quickly.
Pros: 18" as described. Flexible and seems like it is good quality.
Cons: I don't think I actually got 25 feet as described. I only needed 5 feet and now have 10 feet left over. I didn't measure it before I started but it does not add up.