12" Combination Triangular Scale Rule for Mechanical Engineer (1/8, 1/4, 3/8, 1/2, 3/4, 1) and 1:50 Essential tool for Mechanical Engineer or Architect. Compare to Staedtler and Helix and Alvin 12 inch triangular scale beveled edge Includes Open divided ( 1/8, 1/4, 3/8, 1/2, 3/4, 1 = 1 foot.) and 1:50 scale Machine engraved divisions, colored groove Made in Japan