Starrett C33H-6-16R 6-Inch Combination Square with Forged and Hardened Steel Head steel With reversible lock bolt, scriber, spirit level Graduation: No. 16R - quick reading 1/32", 1/64", aircraft quick reading 1/50", 1/100" The square head are forged hardened steel with smooth black enamel finish Square blade easy-to-read, sharp graduation Bearing surface is accurately ground Graduation type: 16R Graduations: Quick Reading 32nds, 64ths, Aircraft Quick Reading 50ths, 100ths Smooth Black Enamel Finish Satin Chrome Blade Forged and Hardened Steel Head With reversible lock bolt, scriber, spirit level