Cello Platinum 6 Instruction Manual page 24

If LED light is not working, the battery should be replaced.
B. Change the LED battery
1. Find the battery box inside the cabinet at the left side, open the lid.
2. Put 4 pcs "AA" size battery, the positive and negative pole of the battery should keep the same
as the pole in box.
3. Close the lid.
CELLO
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