Hi OF I’ve been fascinated by the original Defy line of watches for some time now and thought I’d put together a thread based on my observations from researching them online. I don’t believe any of this information is necessarily new but having it in one place should make it more accessible for those interested. For this thread, I’ll be focusing on the Octagonal case style that was made between 1969 and 1975. There were three other case styles also produced during this period – the Barrel case, the Spaceman, and the TV style. Personally, I find the octagonal cases to be the most reminiscent of 70’s design. Crown at 3’o clock position: The early ones come with the cal 2552 PC movement that beats at 21,600 bph. There are five different dials – khaki and white with chunky markers, and white, brown and black/charcoal with elongated markers. Khaki (A 3642) White (A xxxx) White (A 3643) Brown (A 3644) Black/charcoal (A 3645) The later models have the upgraded cal 2562 PC movement that beats at 28,800 bph. There are five different dials – khaki, white, black/charcoal, turquoise, and burgundy. Some have the elongated hour markers while others have the square, chunky hour markers. Notice the 28,800 printed on the dial. Khaki (A 3642) White (A 3643) Black/Charcoal (A 3645) Turquoise (A 3690 - reference number unconfirmed) Burgundy (A 3691) Then there is the 18k gold version available for both men and women. The men's version comes with either a gold or dark green dial while the women's version comes with a white dial. Men's, Gold (G20672) Men's, Dark Green (G20672, same as the gold dial) Women's, White (ref needed) Lastly, there are two SS women versions that come with a brown and blue dial. Brown (AX 3678) Blue (ref unknown) Crown at 4:30 position: The Defy sub-sea line has the octagonal case but with the crown at 4:30. It also has different style hands and bakelite bezels. There are four different dials: white and black with the roulette bezel, and orange and black that are mirror images of each other. White (A 3646) Black (A 3646, same as the white dial) Orange (A 3648) Black (A 3648, same as the orange dial) The Sub-Sea line also includes two other references which were released later. These don't have a bakelite bezel and have unique hands. The dials are blue, beige and black. Note the reference numbers used for these are based on the newer reference system that was introduced by Zenith in 1972. Finally, the movement used in these is the automatic cal 2572 PC. Blue (01.1500.380) Beige (01.1501.380) Black (01.1501.380) There also exists another Defy with the crown at 4:30 that isn't classified as a Sub-Sea. This single reference has a blue dial with a silver minute track. This reference comes with either the cal 2552 PC or the cal 2562 PC. Blue (A 3651) w/ cal 2552 PC Blue (A 3651) w/ cal 2562 PC A couple notes to end: - The information in this thread has been pulled together from various pages around the web. If an example is missing or if information is incorrect, I'd appreciate your help to make this thread more accurate and comprehensive. Also, I realize there is a book called Zenith: Swiss Watch Manufacture Since 1865 by Manfred Rossler that contains valuable information on the topic. I have not referenced it here as I do not own a copy. - Pictures are the property of their rightful owners and are borrowed for educational purposes.