Product review (1 stars): WILL NOT WORK with 8 foot ceilings! Do Not Buy
The chimney sections are 20 inches tall. If you are thinking of using this in a home with 8 ft ceilings, DO NOT BUY IT!!! The manuals clearly illustrate the commonly supplied two piece chimney sections which SNAP TOGETHER around the mounting angle irons. This hood will not install with only one chimney section and allow the recommended 30 inch clearance above a gas range.
Support is useless in this case. They cannot fathom that the illustrations show two piece snap together sections. The illustrator draftsman sure knew it!  No, they will not arrange for a different part. You either have to lower and use both telescoping sections or return the hood for refund.  Sucks.