Brother MFC620CN Service Manual page 363

(3) Serial number label for ink cartridges
Location
Product code
Barcode
App. 1-3
Factory code
Production year
(Example) 05 : 2005
Production date
(Example) 11 : 11th
20 : 20th
Production month
A : January G : July
B : February H : August
C : March J : September
D : April K : October
E : May L : November
F : December
June M :
Lot information
06 : 2006
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