Johnson Level & Tool 1904-0700 7-Inch Johnny Square, Professional Easy-Read Aluminum Rafter Square w/out Manual ACCURACY AND DURABILITY: This aluminum rafter angle square boasts a solid aluminum body with CNC machined edges for greater accuracy and durability for any job or worksite BUILDERS AND CONTRACTORS: Thick edge is useful as a saw guide. The etched protractor scale can be used directly with the saw against the square for cross or angled cuts. Scribing notches can be used indirectly to create a saw cut line for rip cuts SIMPLIFY STAIR LAYOUT: The Johnny Squares integrated distance and angle scales let you quickly and accurately mark your cut lines on your stringers and, of course, this rafter square has scales for cutting hip, valley and jack rafters ADDITIONAL FEATURES: Permanent graduations with easy-to-read numbers, continuous scribing notches  ideal for ripping at 3-1/2 and 5-1/2, 2x4 board dimension markers for measuring 1-1/2, 3 and 3-1/2, low-glare protective powder coated finish