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