Unrolled curved surface of symmetrical vent adapter from round to rectangular pipe shapes.
It is cut out on sheet metal with further circular rolling.

vent adapter cross section
Sheet thickness (s)
mm
Round base outer diameter (D)
mm
The outer side (A) of the rectangular base
mm
The outer side (B) of the rectangular base
mm
Adapter (H) height
mm
Number (n) of separation parts of surface
point
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