the Egiziano the "diving" tag comes with it. At that time, the dives were "down and up" and at depths that didn't require..safety stops or decompression stops (if they did they were serious stuff). At the time the 024A came out they....exsisted
A multilevel dive i.e. up and down and up and sideways, requires a "safety stop" at 5 or 3 meters. The length of the safety stop varies between the 3 and 5 minutes (90% of the cases). So a graded bezel tells you EXACTELY how long was the stop
