As someone who has cataloged literally thousands of Seikos building the WatchSleuth website it is my opinion that there is no rhyme or reason behind the model numbers other than the fact that even numbered models have gold coloring in the bracelet/case/bezel while odd ones do not.

The suffix has some meaning (J1/K2/P9/etc) to distinguish between variants made in (or intended for) different regions or to distinguish between variations in the strap.

 

Thanks shellerik, kinda what I was thinking since I couldnt find anything on line about it. Gotta say your web page is very well done. I never knew there were this many Seiko variations. I will be spending some time researching models on there, Thanks.

 

From what I've come across mostly models with 4 letters in them before the 3 digits are for the Japanese market, 3 letters for export market. Being Japanese they don't use the number 4 in their model numbers. 001 is usually black dial...

all to be taken somewhat loosely

 

It seems that the sole reason behind the numbering system is to cause me a degree of confusion.

 

For Grand Seiko, the letter after the SBG denotes the type of movement. For example, the A in your SBGA031 means Spring Drive. R means automatic, H means automatic hi-beat, J means automatic hi-beat GMT, M means automatic GMT, E means Spring Drive GMT, C is chronograph (Spring Drive at the moment, since there is no mechanical chrono GS).

Someone can correct me if I'm wrong. I think some knowledgeable person posted a list of these codes a while back. I guess other Seiko lines have similar letter codes. I don't know if the numbers mean anything.

 

S means seiko

 

'SSC' seems to be "Seiko Solar Chronograph" but I wouldn't bet the house on it.