This 20x44mm. Vintage 1940’s GRUEN Doctor’s Watch is known as the “Techni-Quadron”. These watches were essentially the same as the ROLEX PRINCE and houses the (same as ROLEX) AEGLER manual winding EXTREMELY fine movement, which is interchangeable with the ROLEX PRINCE. The dial retains the original raised gold toned BREGUET style numerals with the printing only restored. The hands are original. The gold filled case looks fantastic overall. The movement was just cleaned and is accurate. These watches are highly sought-after.