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ec 425Model: EC-425
Battery: 3 x AA nicd
Adapter: AC9130 
Year: 1974
Chip: TMS0120
Info: The EC-425 is easily identified as a close relative of the TI SR-10, as is the Montgomery Ward P300. Both calculators use the same electronics, the same layout of the keyboard and even an identical mold for the housing bottom. The different look is achieved through a new mold for the upper half of the housing, shared with the Ward P300, and a different color of the function keys.