Product review (4 stars): Helped get back 4 inches of lost space
As other reviews have stated, it is a little on the flimsy side with a number of small spots for air to blow out, but a bit of aluminum tape fixed that just fine (you should probably be doing this anyway to prevent air leaks). At 2 1/8 inches wide, it is less than half as wide as vent hose (but at 6 inches tall has about the same volume for airflow) and allowed me to get back 4 inches of space in front of the dryer!