Sony VGC-RB64GY - Manual (Page 100)

Do not mix old (used) and new batteries when replacing batteries in the wireless mouse. Always use the same
type and manufacture of battery — do not mix alkaline with manganese batteries. Using incompatible batteries or
mixing used, new or different types of batteries can damage the mouse.
1 For wireless or standard optical mice.
2 Operate the mouse, VGP-WMS1, within 3.2 feet of the computer.
Operate the mouse, PCVA-MS2, within 2.5 feet of the computer.
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