OMEGA. A VERY RARE STAINLESS STEEL AUTOMATIC DIVER’S WRISTWATCH PROTOTYPE WITH SWEEP CENTRE SECONDS, DATE AND BAKELITE BEZEL SIGNED OMEGA, AUTOMATIC, PROFESSIONAL, SEAMASTER 600, REF. ST 166.077, MOVEMENT NO. 0002350, CIRCA 1970 Movement: cal. 1000, automatic, 17 jewels, signed Dial: signed Case: large monobloc, 55 mm. wide, 45 mm. overall length, signed With: Omega Extract from the Archives describing the watch as a Prototype of the Seamaster “Ploprof” intended for testing by professional divers.