The JOHNSON Combo Square helps you tackle any job with accuracy and precision. Its 12" stainless steel blade has permanent English and metric graduations of 1/8", 1/16", 1/32" and millimeters for reliable measurements. The durable acrylic vial, heavy-duty cast zinc head, chip-resistant e-coating finish, and hardened screw-in scriber combine to make an incredibly resilient tool. Thanks to its CNC machined square head and Auto-Lock™ blade assembly, you can trust that your measurements are precise and accurate every time.