On June 13, 2008 on auction. One of my favorites:

The Lotfinder sez:

JOSEF HOFFMANN (1870-1956)
¡®Sitzmaschine¡¯ A Stained Beech and Bentwood Adjustable Armchair, designed circa 1908
model no. 670, with hinged adjustable back, manufactured by Jacob & Josef Kohn
approximately 40½ in. (103 cm.) high
Lot Notes

cf. D. Ostergard, Bent Wood and Metal Furniture: 1850-1946, New York, 1987, p. 258 for an illustration of this chair model.
C. and P. Feill, 1000 Chairs, Cologne, 1997, p. 129 for another illustration of this model.

Estimated at $12,000 - $18,000

Keywords: China Office Chairs  Office Chair  Discount Office Chairs  Mesh Chair  Leisure Office Chair  Contemporary Office Chairs  Swivel Office Chairs  Office Chairs  Mesh Office Chair  Operators Chairs  Operators Office Chair