Sony PCV-LX920 - Manual (Page 37)

Erase Operates as an eraser.
Ignored No function is assigned.
Note:
The Left-Click function is assigned by default to the pen tip. Before you change the pen tip setting to perform a different
function, assign the Left-Click function to another switch. Sony suggests assigning the Left-Click function to the pen tip
when using the pen with drawing applications.
Note:
You can reset your VAIO ® Pen functions to the default settings by using the "Reset Tab to Default" button. You can revert to
a previously saved setting by using the "Revert Tab."
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