Review on Enhance Welding Precision with Palmgren 55501 Fillet Weld: Available on AmazonUs ERCT9 by Jim Reinhardt

I like this gauge because it measures both convex and concave welds. It also helps determine the clearance that may be required for butt welding. Yes, it has a screw cap, but other than that it's a good caliber. When used in conjunction with angle gauges, this is all you need to measure welds.