The Juvenia 11511 watch movement, utilized from 1966 to 1970, was acclaimed for being the thinnest automatic movement during its introduction. It boasted a micro-rotor mechanism with four ball-bearings and featured Girocap combined settings for the escapement wheel. Additionally, its indirectly driven minute hand allowed for a low profile. Although there are no known differences between the 231 and the 2301, the specific functions of the movement are not elaborated upon.