Inside case back: "Ref. 2210, 510159, Patek Philippe & Co., Geneve, Swiss, 18K, 0.750, 29". Movement: " No. 942791, Patek Philippe & Co., Swiss, Geneve, Eighteen 18 jewels, Eight (8) adjts." There are also a couple of Swiss hallmarks. Working order. needs a cleaning. Weighs 25 grams.