This 10''' movement is the smallest and slimest movement ever made for a minute-repeating watch.What is a Minute Repeater?A minute repeating watch tells the time both visually and audibly. A slide on the side of the case, usually near the #9, will activate two hammers in the movement. These hammers strike two gongs curled within the case. First one hammer strikes a gong of lower tonality; it will count out the hours. Then both hammers will strike both gongs alternatively to count out the quarter hours after that hour, and then the second hammer alone striking a gong of higher tonality will count out the minutes aftr that quarter hour. The repeating mechanism was developed by Daniel Quare. In 1687, he had patented a mechanism that sounded the hours and the quarter hours. The early repeaters used bells. At theend of the 18th century, two bent-wire gings became the more popular mechanism. In 1892, the first minute repeater wristwatch was produced by Omega, a model with a round-shaped case.Audemars Piguet started making miniature minute repeating movements at the beginning of the 20th century. From 1906 to 1920, some 35 minute repeating movements were made in their workshop. 20 of them were to equip wristwatches.Two previous identical movements of minute repeating wristwatches are illustrated in "Audemars Piguet", by Gisbert L. Brunner, Christian Pfeiffer-Belli and Martin K. Wehrli, p. 256, The N° 16976 is retailed by Gübelin, and the N° 16977 is made for Cartier.