Need a new 109(?)

[Open Ocean Diver]

Update:

My source was not absolutely sure about the numbering system, but here are a few clues.
A s/n with 6, 7, or 10 numbers: The first number indicates the production year-so one has to have an idea of which decade his regulator was produced in. So in the examples given by @Open Ocean Diver:
BA SN 5907469 <--probably 1985 unless it is a very late model which might make it 1995 (does it have a satin finish?)
108 SN 481669 <--probably 1974

Eight digits: the first 3 digits indicate the Julian date*, Digits 4-5 indicate the year, 6-8 indicate the production number.

9 digits? I do not have any information on those.

*Julian date: the day number of the year. E.g. today 09 Aug 20 is the 222nd day of the year)

The BA is all shinny Chrome.

Thanks for the info

Here’s my BA with a satin case finish and a 10 digit SN. Any ideas how to decode this one?

 

[Couv]

A s/n with 6, 7, or 10 numbers: The first number indicates the production year

So probably produced in 2000.

 

[Open Ocean Diver]

So probably produced in 2000.

Right makes sense. Thanks

 

[axxel57]

So probably produced in 2000.

Strange.....
The production of the 156 was stopped in 1998 afaik........
From 1999 to 2009 SP didn't offer any 2nd with metal housing.
Anyway, what a beauty....!

 

[Couv]

Strange.....
The production of the 156 was stopped in 1998 afaik........

Well, that's what I thought too; however I don't really have any references to confirm that. The only source I can find is the old "SP Timeline document" known to have mistakes. But it does mention the Balanced Adjustable being available up to year 2000. See attached document.