Probably South German or Austrian, 18th century

Overall the condition of the iron is good, with wear throughout and minor dirt consistent with age. There is minor corrosion to the metal, in particular at the back. There are nicks and minor dents throughout. The knocker slides loosely into the mount with its original screw at the back. The perspex mount is in good condition with some wear.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

RELATED LITERATURE
H.R. d'Allemagne, Ferronnerie Ancienne, cat. Musée le Secq des Tournelles, Rouen, Paris, 1924, vol. 1, pl. CXXVI