The "Grand Réveil" model was launched in 1989 and features a unique alarm mechanism for a wristwatch, a bell struck by a hammer. It was the first automatic wristwatch combining a perpetual calendar and alarm.
The gong is made of a special bronze alloy already in use during the late Ming Dynasty in China because of its long lasting resonance. It is suspended inside the case allowing it to vibrate musically when struck by the hammer.
The model is illustrated in Armbanduhren - 100 Jahre Entwicklungsgeschichte by Kahlert, Mühe, Brunner, fifth edition, p. 444, pl. 1532.