These chronographs have the chronograph minute recorder at the top and the running seconds recorder at the bottom
1940s -- Up / Down Chronographs
Up / Down Chronographs -- Early Models
The early models of Heuer's up / down chronographs are powered by the Venus 170 movement (12.5 ligne), and have the "Heuer" shield below the top recorder. Measurement across the dial is 32 millimeters.