Product review (5 stars): Excellent product function
With only having a few inches of available space, this item has a perfect fit and function for the small laundry closet space in my RV, would also work for small apartments or simply any area with limited rear clearance.  Without this, the 4" air vent hose would be crushed between the machine and wall.  Very easy to install, all parts needed are included.

The item also rotates at the machine end, allowing for ease of access at the rear to clean, reach for missed items or install shipping bolts when moving (for example - RV).

The air flow in small dryers or washer/dryer combos is low enough where the 90 degree turn on this item doesn't inhibit flow enough to cause any bit of an issue.