What do I have?

[USdiver1]

USD's serial numbering system was at its best excellent, and at its worst non-existent. There are double hose regulators from the late 1950 with no serial number ever issued, and there are single hose regulators from the 1970s and 1980s where each stage (1st and 2nd) main body will have year specific prefixes in the serial number (e.g. 77XXX denotes a 1977 manufacturing date). The problem is that while the serial numbering system changed over the years, the archived records are incomplete, so dating a particular regulator's year of manufacture is an estimation. Best to list your serial number and perhaps someone may have an educated estimate of the manufacturing date.

 

[JohnnyC]

USD's serial numbering system was at its best excellent, and at its worst non-existent. There are double hose regulators from the late 1950 with no serial number ever issued, and there are single hose regulators from the 1970s and 1980s where each stage (1st and 2nd) main body will have year specific prefixes in the serial number (e.g. 77XXX denotes a 1977 manufacturing date). The problem is that while the serial numbering system changed over the years, the archived records are incomplete, so dating a particular regulator's year of manufacture is an estimation. Best to list your serial number and perhaps someone may have an educated estimate of the manufacturing date.

Only number on the thing is on the yoke. Reads 12283, or maybe 89. What does that mean? Made in 83 or 89? I thought they were well past the VI by then.

 

[txgoose]

This was the post I was thinking of.

The Conshelf VI was available from 1966 through 1969. In 1970 it was replaced by the Conshelf XI. These USD catalogs (1960-1979) are available on CD from VDH.<snip>

They may not have been putting year of manufacture in there yet. I may just have to be happy knowing that the VIs are '69 or earlier.