The following two lots, 337 and 338, are fitted with the celebrated "Auto-Prince" calibre 390, a 17 jewels movement developed by Rolex in the 1950s for Tudor. As reliable as their "sisters" signed Rolex but available at a lower price, Tudor diver's watches were the brand of choice of many armed forces, particularly certain units of the French and the U.S. Navy.
The brand Tudor was introduced by Rolex around 1945 with the aim of supplying high quality watches at affordable prices. Although Rolex never advertised their connection to Tudor, they however supplied, amongst other parts, the Oyster cases and crowns. The symbol of the brand was the Tudor rose until around 1960 when it was replaced by the shield which is still in use to date. The line of models comprised also Submariner and Cosmograph watches considered as reliable and durable as their "big sisters". Made in much smaller series, these watches have become extremely popular amongst collectors.