Mid to late 70s Defy. Should have a 2572 pc movement. The black dialed model has a serial number of 02.0360.380, so I would expect your version to have a similar number with the middle section slightly different. In terms of value, it's not super collectable (unless you're looking to get all the Defys). That said, the last one sold on eBay was black dialed, in mint condition and listed for $826 (it sold for less on a "Best Offer").