The Unitas 83 watch movement is an open face calibre with a stop function, featuring a pillar wheel. It includes a glassed spare-parts compartment. These movements are commonly attributed to Leonidas, but they bear the Venus signature, suggesting that they were likely manufactured by Venus, potentially exclusively for Leonidas. The movement offers various timer options, such as 60s (0.2s) with a 30min capacity, and additional options for 30s (0.1s) with a 15min capacity, 10s (1/30s) with a 5min capacity, and 3s (0.01s) with a 3min capacity. It also includes an option for an addition timer. The Unitas 83 movement is stem-wind and features a sweep second hand. It was predominantly used during the period around 1930.