The G.A.L. Gage Co. Cat # 4a Pocket Bridge Cam Gauge GAL-4a, Inch & Metric is a unique, versatile, easy to use instrument. It measures angle of preparation, 0 to 60 deg., excess weld metal (capping size), depth of undercut, depth of pitting, fillet weld throat size, fillet weld leg length and misalignment (high-low). It measures in both inch or millimeters.