Create 4 inch or 8 inch square on square blocks. No calculations needed - all the cutting measurements are printed right on the tool! Trimming each round as triangles are added creates perfectly square, uniform blocks. The popular Snail's Trail block is now easier than ever - simply change the colors of the triangles! The ruler slides easily over the fabric until pressure is applied. Then, our exclusive gripper holds the fabric in place while cutting, eliminating slipping and miss-cuts! It comes with fully illustrated step by step instructions or scan the QR Code printed on the tool to view a video demonstration.