POWERTEC 71080 Plastic Center Locator - a set of tools for wood turning - a very handy tool. This is a very simple design, but it works very well. I've used it for "cylindrical" woodwork. Pros: Very easy to use. Attractively priced. Continuous. Cons: If you want to be fully transparent, it's opaque. You can see through a bit, but it's shady. Overall, my rating is a five. A good and effective tool for what it is intended for.