Combination Set Number of Pieces 4 Blade Finish Brushed Blade Material Steel Head Length 4 1/2 in Head Width 3/4 in Blade Length 11 3/4 in Blade Thickness 0.09 in Blade Width 1 in Graduation Mark Style Etched Graduation Marks - Front 1/2 mm 1/32 in Graduation Marks - Back 1/64 in Head Type Center/Non-Reversible Protractor/Square System of Measurement Metric/SAE Head Material Cast Iron Includes Blade Non-Reversible Protractor Head Head Vial Included Yes Accuracy +/- .0025 in