Silver screw vs backplate

[Pepe]

Thanks for the idea, fernieite!

[fernieite]

Thanks for the idea, fernieite!

Glad to help.

[sebastien32]

https://www.stompboxzone.com/decoder/

Have you tried the link above?
Looks like November 1980. Are your 10000 ink stamped or stickers?

@pepe, shouldn't we have a sticky for the boss serial decoder, like the old days?

Yes I know about the decoder. I was more asking about stamped serial "10000" vs "0000" that are for the same period.

[Old_Iron]

Do you have detail about stamp serial #10000? I have 2 silver screw with that number.

The reason Boss used stamped 5 digits batch numbers for a while is unknown.

Probably, it was the idea to continue to use a stamp as a tool, to print the batch numbers, after the stamp they have been using reached 9900.