This is a wonderful paper trimmer.  I use it daily in my scrapbooking and card making hobby.  The trimmer is a full 12 inches but folds along the line that you can use for scoring, making it easy to store and carry. 

The blade self sharpens with each use, which is a HUGE plus for me.  No more worries about finding the correct blade and changing it out myself.  

The unit comes with a magnetic ruler which is very handy, but be careful that you pull it directly off the paper rather  than trying to slide it, as it will marr your paper.

The grid is very functional and the templates applied...