Number of Pieces 4 Blade Length Inch 12 Graduation Style 4R Graduation Inch 18, 116, 132, 164 Blade Length mm 300 Graduation Protractor 1Deg, Blade 8ths, 16ths, 32nds, 64ths 4R Blades are hardened and tempered for durability Square head has level and pointed attachment for hand scribing Microfine blade graduations Gauge heads are hardened cast finished in baked enamel with exception of the measurement faces