The fence gets docked to the correct length with the first cut (photo #2). From then on you never have to account for the saw base/blade offset. Just mark wood to length, put the tip of the fence at that mark, and the ChopShot guide will automatically be at the correct offset to match your saw base (photo #3). The design ensures good reference to the board edge while lying stable on the workpiece.
Made of hard-anodized aluminum, it measures 14" x 8" and has an accurately milled edge that is 3/16" thick. It is compatible with all saws, left or right cut; it even works with saws that have stamped base plates with rolled edges. Intuitive to use, it is like having a chop saw at your work site. Screws and complete instructions included.