The UltraTest Combination Measuring Set brings you the power of a square, ruler, protractor and centering gage in one convenient design. The hardened and heat-treated heads attach to the 12” satin chrome blade for taking a variety of measurements with ease. The Square Head provides 45 and 90 degree angles and also features a level and hardened scriber. The reversible Protractor Head measures odd angles with precision accuracy, and the Centering Head allows you to find the middle of round stock. The set also includes a locating screw on each head for faster attachment to the blade.