The Junghans 688.70 watch movement, produced from 1916 to 1974, is a manual-wind chronograph with a 60-second and 30-minute counter, incorporating a pillar wheel mechanism. It also features a sub-second display and the option for a single pusher at 2 o'clock. The VZ is considered to be an early version of the 23 movement, sharing similar characteristics except for the coupling clutch. While the VZ designation is commonly used in Valjoux data sheets, it is occasionally referred to as the 23VZ. Over 125,000 units of the Junghans 688.70 movement were manufactured during its production period.