I bought another Shinwa sliding bevel that has a locking mechanism in the head. The locking mechanism got in the way when using the tool, so I decided to try this model. This is the fourth Shinwa instrument I have purchased and they are all very high quality. The locking mechanism on the underside of the base allows this tool to do any job that I couldn't do with any other sliding bevel. The tool is easy to use and the locking mechanism keeps the blade secure. highlighted.