Product review (5 stars): Does the job
I bought this to go with the&nbsp;<a data-hook="product-link-linked" class="a-link-normal" href="/Broan-PM390-Power-Pack-Range-Hood-Insert-Silver/dp/B000R9CFL6/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Broan PM390 Power Pack Range Hood Insert, Silver</a>.  I bought an older home that had an empty-inside wood hood (no over stove cabinet) and thought this liner would slip right in there, we pop the fan in, and that's it. I downloaded all the instructions, spec sheets, etc., I could find online ahead of time.

The instructions (both from the web and from the box) are confusing.  We weren't even sure which end was up (looks different in different drawings).  My contractor had to call the 800# for advice and that person told him that the insert is not designed to hold up the fan.  He said you have to either have a cabinet or build a box.  In effect, this liner is just to cover up the wood, protect it, and give a stream-lined look.

After some discussion we decided to just use the liner to hold up the fan and it seems very solid. The liner installs with the opening pointing down (concave), so the bottom of the fan unit ends up 4" above the bottom of the hood and is hidden.  I posted some photos.

It's slightly awkward reaching under and/or looking under to locate and move the switches which are on the bottom of the fan unit.  I'm sure it will become automatic with use.  It seems that the fan and therefore the lights sit further back (nearer to the wall) than when I had a standard under-counter fan unit.

For my situation, this liner combined with the fan were perfect.  The finished project looks very professional and was way less costly than a custom hood.  It was not possible to find a matching cabinet in order to install a ready-made fan unit off the shelf.  The cost for this liner, the very nice fan unit, and labor was less than or equal to what it would have cost for an off-the-shelf fan unit, non-matching over-stove cabinet, and labor.