Description: Ten (10) character Serial number begins with four (4) numerical digits followed by one (1) letter and ends with five (5) numerical digits.
Week of manufacture is 1st-2nd character numerical digits.
Year of manufacture is 3rd-4th character numerical digits
Style 2: 850304091
Description: Nine (9) character all numerical Serial number.
Year of manufacture is 1st-2nd numerical digits
Month of manufacture is 3rd-4th numerical digits.
Style 3: W4D14008 (Only used from 1980 – 1984)
Description: Eight (8) character serial number begins with one (1) letter followed by one (1) numerical digit and then another letter digit and ends with five (5) numerical digits.
Month of manufacture is 1st digit of the serial number. (See chart below).
Year of manufacture 2nd digit of the serial number. (See chart below).
Style 4: A167890 (Only used from 1970 – 1979)
Description: Seven (7) digit serial number that begins with a letter and ends with six (6) numerical digits.
Month of manufacture is the first letter digit. (See Chart Below).
Year of manufacture is the second digit. (See Chart Below).
Style 5: 6###### (Used prior to 1970)
Description: Seven (7) digit all numerical serial number.
Year of manufacture is the 1st digit of the serial number.
Style 6: 46U152456 (Used from 1960-1979)
Additional Example: 2W 13270
Description: First two or three characters consist of one or two digits preceding a letter.
Year of manufacture is the second or third character (letter) of the serial number. First one or two digits represent week of manufacture. The sample serial number above was from a unit manufactured the 46th week of 1967. The second example was manufactured the 2nd week of 1969
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