Marcel Breuer, Model B3-Chair, also known as the Wassily Chair, 1925-1926. Originally produced by Thonet, Germany, in bent tubular steel and canvas. Italian Gavina Group bought the license for Wassily after the WW2 and replaced canvas with leather straps as the chair is most famously known nowadays.
Think I prefer this canvas version.
Photo copyright by Scandinavian Collectors 2016.