Product review (4 stars): No more night sweats / heat diverted
Night sweats, no more.  I have a vent under my bed.  Pair it with my foam mattress and during the winter, I would feel like I was cooking on the grill!  Yes, it's just plastic, but it serves its purpose and works great, as intended.  It comes with two pieces and extends really far.  I do wish it was sturdier and that the clip worked better to hold it together, but overall, it works, so it's great.