Fussy cutting is a breeze with our 6 1/2” square ruler, with a 3 1/2” window in the center. The interior corners have teardrop-shaped cutouts, so that you can safely and easily use your rotary cutter to cut out the perfect square for your project. The ruler is accurately marked with 1/8” guidelines in a one-inch grid. It’s a hardworking, multifunctional tool you’ll be glad to put in your toolbox.