Exactly such chairs we always had in our Handzgi studio. Well, not so dark - rather it was the natural sibling of this black chair you see here. And I can assure you, they can withstand a lot and are also stackable.
A timeless classic from 1934 designed by the architect Gustav Hassenpflug. He studied at the Bauhaus in Dessau and revolutionised Swiss schoolroom furniture in the 1930s.
The clear form of the Hassenpflug chair convinced me even then in the Handzgi room and I still like it quite much as a single object at my desk. The German architect designed this chair for the traditional Swiss company Embru, which still produces and sells this classic classroom chair today.
The dark varnished structure of the Hassenpflug chair consists of round steel tubing, which is covered with two black stained beech wood elements. Due to the concave shaped plywood the chair is quite comfortable and therefore perfect for the dining table.