MiLAN 1503109 Manual Del Usuario página 14

In the event of malfunction, please press the "RESET" button on the
back of the calculator.
Power: 2 type LR1130 batteries
HOW TO CHANGE THE BATTERIES:
1) Unscrew the six screws from the back cover and remove cover.
2) Remove the used batteries from their compartments.
3) Insert the new batteries, with the poles in the correct position
(the positive pole must be visible).
4) Replace the back cover and screw in the six screws.
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