Sony VGN-A140P - Manual (Page 28)

To set up the wireless mouse
Insert two AA batteries (supplied with the mouse) into the wireless mouse as shown.
Inserting batteries into the wireless m ouse
If your wireless mouse does not operate properly, the batteries may need to be replaced. When your wireless mouse
is not being used for extended periods of time, remove the batteries to avoid possible damage from battery leakage.
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