Ref. 130Production of this reference started in 1934.Similar watches are published in Patek Philippe Wristwatches, by Martin Huber & Alan Banbery, 1998 Edition, pp. 262-264and 269.Wristwatches with concealed dialShortly after 1920, wristwatches were selling better than pocket watches. Most eminent designers and makers were keen to find, for sport and everyday wristwatches, an equivalent to the popular hunting cased pocket watches which can easily be personalised with a monogram or enamelled decoration on the cover.Cartier and Verger, in France, used improvements such as the guillotine with sliding shutters, already invented for dress watches, and Léon Hatot, with the Montre bracelet ouvrante, featuring a spring loaded hinged cover, presented his own solution. Cartier, with its Savonnette model, also used a hinged cover, without it being spring loaded.Hatot's solution was also adopted by most of the Swiss designers such as Wenger, Niton as well as those working for Vacheron Constantin and Patek Philippe.In this respect, one of the most successful solutions was that of the celebrated Reverso invented by René Chauvot (French Patent No. 712868 from March 4, 1931), first produced by Fontainemelon S.A., often retailed by Gübelin, and then acquired by Jaeger LeCoultre.The cases of most of the watches with concealed dial, produced between 1920 and 1935, were of high quality, often with engraved decoration on the band and bezel; the cover was sometimes made in two-coloured gold with geometrical decoration in an Art Deco pattern.