Johnson Level 400 12" Combination Square - Heavy-duty Cast Zinc Head With Scriber. The Johnson Level 400 is a 12-Inch Cast Zinc Head Combination Square Features: Heavy-duty steel blade with protective anti rust coating is permanently etched in graduations 1/8", 1/16", 1/32". Heavy duty cast zinc head with black chip-resistant e-coating finish, CNC computer machined square head gauging edges for greater accuracy, Reversible head with lock bolt and steel screw, Hardened, screw-in removable scriber won't fall out, Durable Acrylic Yellow Barrel Vial, What's In the Box: Johnson Level 400 12-Inch Zinc Head Combo Square with Scriber.