Sony VAIO VGCRB40 Owner's Manual page 210

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.
For wireles s or s tandard optic al mic e.
1
O perate the mous e, V GP -WM S1 , within 3 2 feet of the c omputer.
2
O perate the mous e, P C V A -M S2 , within 2 .5 feet of the c omputer.
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