Product review (4 stars): Great Space Saver
I've been fighting unruly flex hoses behind dryers for years. Finding this was wonderful. It was very easy to install (I was cutting a new hole in the wall anyway, due to moving machines around). It saves a ton of space.

It comes with two clamps, but they seem superfluous. In my case, the dryer itself holds it in place firmly, and I could never get my hands into the space between the wall and the dryer to tighten them anyway.

My only quibble is that it is made of VERY thin aluminum, and so it is fragile. You have to be careful or you'll bend it. Once in place, though, it should be fine for a long time--unless I forget about it's fragility and yank the dryer out less than very carefully, someday.