Staedtler STD9871931BK Architects Printed Scale 12-Inch triangular scale in Staedtler's student series is ideal for students of architecture Three sides with six different scales feature die-engraved graduations Easy-to-read printed graduations will not rub off Architect triangular scale is open divided: 3/32-Inch, 1/8-Inch, 3/16-Inch, 1/4-Inch, 3/8-Inch, 1/2-Inch, 3/4-Inch, 1-Inch, 1-1/2-Inch, 3-Inch = 1' Measurements are fully divided in inches to 16ths. Triangular scale is made of high-impact polystyrene plastic