Sony VGC-RA840G VAIO User Manual page 240

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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