The revolutionary Incra 18 Bend rule has precision-engineered marking holes and slots at every graduation to guide your pencil or scribe making it nearly impossible to slip off the mark. Repeat measurements will always be exact and no more eye strain! Try one. You may never use an ordinary rule again! This concept rule makes around the corner and edge marking absolutely foolproof! Marks 2 sides at a time precisely in line. The stainless steel blade is graduated in 1/32 increments. USA