ORATOR AQUA-LUNG REF. 2501/1. LATE 60'S Diver's wristwatch with steel chronograph. Case: round, screw-down back, pump pushers, black rotating bezel graduated for compression times. Dial: black lacquered, two counters, tachometric scale. Movement: mechanical, cal. Landron 248, shock-resistant movement, 17 jewels. Without bracelet. Dial signed. Diameter: 39mm