Product review (5 stars): Does the job, well packaged, ensure you have tape on hand to seal it
Let's acknowledge the reality that dryer ducting is a pain in the neck. Given that, it's hard to find fault with this dryer periscope. It came packaged well (no dents, etc.) - box within a box within an amazon box. It's relatively easy to adjust to length (measure twice... cut once...). Gloves are recommended since metal edges can be sharp. As other reviewers have noted, you will not get an airtight seal with this thing w/o a bit of investment of your time. Unless you want it to double as a humidifier for the room where the dryer is located, you should anticipate taping it with good quality metal/foil tape (e.g., the 3M/Scotch stuff). This takes a bit of time but is well worth it. The unit comes with two clamps -- a nice touch. Considerations will be different for different "tight spaces" but I found it easiest to install it onto the dryer directly, and then to a short run of collapsible/flexible ducting to allow me to climb out from behind the dryer and then shove it back against the wall.