Filter out all but the first 3 Letter of a Cell

Hi

I have a few Cells. I only need the first 3 letter in this cells everything after is in the way. I tryed to use the Cell Splitter node to filter out the rest of the Cells but i failed.

Is there a way to get only the first 3 letters of a Cell?

Thx 

Suppe  

The node Cell Spliter by Position does this.

Best, Iris