Product review (3 stars): Does it's job some assembly/modification required for optimum performance.
It does what is supposed to but it was going to require significant taping(HVAC foil tape) to not leak. This didn't really work for my application as it wasn't long enough but if you measure correctly and use a couple HVAC ducting screws to set the length and tape the edges it should work perfectly.

I would recommend two screws on the sides to hold the cap on and two screws on either side to hold the pipe to length needed and then a generous application of HVAC tape to make it air-tight. Machine folded construction...