This Festool parallel guide set provides a faster, easier, smarter way to create consistent rip cuts using two adjustable stops that engage the edge of the material parallel to the cut line. They are adjustable up to 25-19/32" (650 mm).The additional Parallel Guide Extensions enable narrow repetitive rip cuts between 1/16" to 7-11/16" (1 mm to 195 mm). I have corrected two concerns I had about the Festool parallel guides: 1st the looseness of the parallel guide itself when cutting narrow stock; 2nd the small gap between the scale and the stop that makes it a little harder to precisely set the guides. This whole parallel guide set retails for $575, my enhancements make it simpler and easier to setup.