The Flex Edge discs attach to the holder with a push and clockwise twist like the regular Power Lock discs, but are designed so the sanding disc overhangs the holder. By having approx. 1/4 overhang around the holder, the Flex Edge disc is not as aggressive as the regular Power Lock discs and is less likely to dig in to the workpiece. The Flex Edge discs come in 2 and 3 sizes and have a padded reinforced area around their edges to provide support for the overhang of the disc. The Flex Edge Discs are available in 60, 80, 120, and 180 grits. Starter Kits are available that include one Flex Edge Holder and 5 ea. of 60 ,80 ,120 and 180 grit Flex Edge Discs.