The 1675 bezel is bi-directional and rotates on a spring-based system. There is a flat shaped piece of metal (the tension spring) that sits under the bezel and holds the bezel/insert in place until the user places pressure down on the bezel to rotate. Unlike later models, which incorporate a clicking mechanism, the rotation is smooth. The bezel itself has an outer diameter of ~39.3 mm with two inner rings, the smaller of which is ~34.75 mm and the larger of which is ~35.15mm. There are two types of bezels:
- Early Bezel (left): the grooves span the entire vertical portion of the bezel. These are seen on examples until around 1963.
- Standard Bezel (right): the cut out portions that are not as deep and do not extend into the base of the bezel. These are seen on all examples from 1964 onward.
Bezel inserts are made of anodized aluminum. The colors are not “painted” on but applied galvanically in a similar process to gilt dials. Generally, the inserts have an inner diameter of ~30.2 mm, an outer diameter of ~37.75 mm, and are ~0.7 mm thick. They should fit snugly into the bezel with a slight lip of bezel retained above it. Inserts do not change size over the production of the 1675.
Red & Blue: The standard Pan-Am or ‘Pepsi’ bezel inserts have only two attributes that are mandatory to be period correct for a 1675 – a red back and oval 8s. During the long production of this model, however, there are several trends for different periods. Let’s review:
- Red backs:
- Both pictures below are examples of period correct inserts.
- Regular inserts (left) should be red and not faded, even if the front is faded.
- Fuchsia inserts (right) are fuchsia underneath.
- Service inserts are blue-backed (not pictured).
- Oval 8s:
- Period Correct (left): the top half of the number 8 is oval.
- Service (right): the top half of the number 8 is round (sometimes called “snowmen”).
- Red & Blue insert trends:
- Early 1960s (top left): The sides of 12 o’clock triangle sit toward the dial and are very bowed and wide and copper tones are seen (but not mandatory).
- Late 1960s to Early 1970s (top right and bottom left): There is no single defining characteristic. The triangles tend to not be as bowed but still sit closer to the dial and are not as narrow as later bezels. The numeral fonts aren’t as tall as the later 70s examples and sit closer to the dial as well. Fuchsia bezels (generally found on Mark 1 matte dials with serials of 1.6-1.9m) and “super fat font” bezels are both seen in this era.
- Mid to Late 1970s: A skinnier triangle, thinner numerals and taller 2s, and more vibrant reds & blues are seen. The ‘leftovers’ of these red backs are also seen on early 16750s.
- These are trends, not dogma. Don’t dismiss a watch if the insert doesn’t match these observations. Take it into consideration as one piece of information when evaluating the cohesiveness of an example as a whole.
Black: Black inserts were produced more commonly starting around 1976. Recently, documentary evidence of black inserts with 1960s insert characteristics and in pictures of a GMT from the late 1960s was found, indicating that black inserts might be seen on earlier examples. This is not conclusive but interesting as the characteristics match those seen on the red & blue inserts of the same period. All these inserts–the (potential) 1960s inserts, the regular 1970s inserts, and the service inserts–have a black back. The 1970s inserts (labeled original insert, below) otherwise hold the same font characteristics as the late 1970s red & blue bezels above. While some consider these to only be service bezels on the 1675, the above documentary evidence suggests that they were at least available to be swapped in at dealers at the time of sale, if not put on at the factory itself.
Blueberry: The originality of these is disputed and I will not be covering them.
Some Fake Bezels