Little tool big results. Johnson s 12 metal combination square gives you the accuracy and precision you need for every job and was designed to be durable for a lifetime of use. Its stainless steel blade has graduations of 1/8 1/16 and 1/32 that are permanently stamped so you ll never worry about them fading or wearing. Similarly the durable acrylic vial heavy-duty cast zinc head with a black chip-resistant e-coating finish and hardened screw-in scriber that won t fall out helps this combo square withstand even the roughest job site abuse. It was also designed with maximum accuracy in mind - its square head is CNC machined for greater accuracy and the Auto-Lock™ blade assembly makes it easier to accurately line up your tool for use.