<lightning:dualListbox  label="Some field" name="some name" 
                       sourceLabel="Available"
                       selectedLabel="Chosen"
                       options="{!v.options}"
                       onchange="{!c.handleChange}"
                       size="20"

Hi, I'm working with lightning:dualListbox , I would like to custom it because the label's options are too long. I haven't found how does it works...

This is an example of my lightning:dualListbox 

Thanks in advance!

Regards