Chimney
Steel core chimneys, which are made out of corten steel, because it provides a long durability.
The chimneys are insulated with foil faced mineral wool, and must be mounted on a cast base with bolts.
They are available in variable height with/without ladder and security.
They are available in different sizes from Ø250 - Ø450, and will typically be included as a part of an overall system.
It is very important that the chimney has the correct dimensions and height to be able to deliver the necessary draft. Size etc. can be found in the boiler manual.