This super high quality tool with hardened steel blade. The head may be locked securely in any position along the blade. Features ul style"margin-top0px; padding-top 5px; padding-bottom 5px;" 6" 4r blade with 4" base graduated in 8ths 16ths 32nds 64ths heavy duty hardened precision ground satin chrome blade made to strict us accuracy standards accuracy 0.0008" per inch bubble level