it depends on your cooktop/range style and size. For me, I have two of these
but an older model: http://www.boucheappliances.com/products/Gaggenau/gag/vl041.htm
they sit in between 3 Vario cooktop units. Each delivers a max 625cfm power
with a under-the-counter external blower. They work/look beautifully, but
are not cheap at all.
