Review on HHIP 4406 0042 Single Edge Finder: Accurate and Efficient Tool for Precise Metalworking by Ralph Gerry

This thing just doesn't work. The spring holds the ends so tight they barely move, and the surface between the wiggler and the main bar has an odd contour. Instead of sliding in and then leaning to the side upon reaching the outermost surface, it seems like it just wants to center sharply and then lean back when enough lateral pressure is applied to it. Completely useless as an accurate edge finder. Spend an extra $0.20 (yes, 20 cents) and buy a Mitutoyo. I did and will return it.