I bought the stainless version of this angle finder. While expensive up front, this tool is one that will last you your lifetime. Solid joints with thicker sheet stainless than your average protractor from the hardware store. Originally I purchased this one and the small one to replace all my digital angle finders. They always seem to run out of batteries when you need them... These ones work way better than any digital one I've found. Plus, when you're working off 1:1 drawings, they actually lay pretty close to flat so they're easy to scribe lines straight form the tool.