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The single digits were used by other manufacturers to designate a year during the 1950s. Thus Almarg appears correct the second set seems to mean made in the 39th week of 1954 and the 22 week of 1955. The first two look like JAN codes both tubes 1958 the 17th and 39th week.
The single digits were used by other manufacturers to designate a year during the 1950s. Thus Almarg appears correct the second set seems to mean made in the 39th week of 1954 and the 22 week of 1955. The first two look like JAN codes both tubes 1958 the 17th and 39th week.