Landeron 71

Cal. 71 is a 14 ligne cam-switching chronograph movement produced by Landeron (Charles Hahn & Cie.) in the 1940s and 1950s. It is part of a slightly-larger family of cam-switching chronograph movements less well-known than the famous and innovative Cal. 48 family. The various Cal. 71 family movements are similar, differentiated mainly by changes to the cam mechanisms, bridges, and plates.