Starrett 11H-6-4R 6-Inch Combination Square with Cast Iron Head and Black Wrinkle Finish With reversible lock bolt, scriber, spirit level Graduation: No. 4R - 1/8", 1/16", quick reading 1/32", 1/64" Cast iron head with black wrinkle finish Square blade easy-to-read, sharp graduation Bearing surface is accurately ground 4R Grad: 8ths, 16ths, Quick Reading 32nds, 64ths Hardened steel, machine divided blade Reversible lock bolt Cast iron head Black wrinkle finish