JAEGER-LECOULTRE Duoplan, movement no. 39569, case no. 61132, circa 1934 A very fine and rare, stainless steel Staybrite, hand wound, lady’s wristwatch with pink champagne dial, blued steel Sword hands, back winder. Fitted with a rectangular mechanical movement, 15 jewels, lateral lever escapement, index regulator, cut-bimetallic balance, self-compensating flat balance spring, protected by a dust cap, hinged case back, back winder, mineral glass. Dial, case and movement signed. Dim. 34.90 x 11.70 mm. Thickness 6.60 mm. Accompanied by a fitted vintage JLC presentation box. The Jaeger-LeCoultre Duoplan movement is a historic and innovative watch movement introduced by Jaeger-LeCoultre in 1925. It was a major technical advancement in watchmaking during the early 20th century, especially for ladies' watches, which at the time were small and often compromised on accuracy and durability. Thanks to its two-level construction (DUO-plan), the movement allowed Jaeger-LeCoultre to create very small movements without sacrificing robustness or timekeeping accuracy.One of the main challenges of miniaturized movements is maintaining precision, The Duoplan solved this by keeping the essential regulating components (like the balance wheel) larger than usual for such a small case.By stacking components vertically, they maintained a relatively large balance wheel and gear train for better performance.