With Patek Philippe Extract from the Archives confirming production of the present watch with silver dial and black Roman numerals in 1911 and its subsequent sale on 8 December 1917. The Extract further states that the watch obtained a Geneva Observatory rating certificate on 20 August 1913. Also delivered with copies of the Geneva Observatory timing sheet and results of the 1913 First Class timing contest where the watch obtained the 3rd prize with 760 points and a variety of other documents, including original letters from Patek Philippe Geneva to Paul V. Shaffer at 443 Marlborough Street in Boston, Massachusetts, dated 9 August 1958, 25 September 1958 and 10 November 1958 related to an overhaul of the watch, original invoice dated 8 November 1958 amounting to Swiss Francs 40 for the latter, Swiss customs export document and US Customs application form for articles to be exported for repairs, both duly filled out and stamped by the relevant authorities. Paul V. Shaffer, a watchmaker located at 443 Marlborough Street in Boston, had requested a cannon pinion for his deck watch which Patek Philippe was only willing to supply upon reception of the entire movement. An evidently meticulous person, Mr. Shaffer had furthermore kept a technical data sheet and various black and white as well as colour images of the watch.
The ébauche of this previously unknown masterpiece was made in collaboration between Victorin Piguet & LeCoultre & Cie. and finished in the workshops of Patek Philippe. The movement is numbered twice, characteristic for Patek Philippe's Extra quality movements participating in timing contests. The balance staff is set with a diamond endstone instead of the more commonly used ruby endstone, a rare feature only found in movements of superior quality.
A similar silver deck chronometer, movement no. 170'283 and case no. 272'024, only two numbers apart from the present watch, is illustrated and described in Patek Philippe Museum - Patek Philippe Watches - Volume II, p. 43, Inv. P-1331. The watch participated also at the Geneva Observatory timing contest in 1913 where it was awarded a Third Prize too. It was sold to the United States Naval Observatory in 1917.