As a saw guide, stair layout tool or rafter tool, Johnson’s 7 in rafter square will help you get the job done accurately and easily. It features Johnson’s unique Structo-Cast® molded frame that is both lightweight and durable as well as permanent molded graduations for making quick and easy measurements. This rafter square comes with handy markers that measure 2×4 board dimensions of 1-1/2 in, 3 in and 3-1/2 in. And you’ll always find this square quickly in your toolbox thanks to its fluorescent, easy-to-see color.