
My cassette lockring came loose due to sloppy work by my former mechanic,so i decided it was worth it to invest in a tool,and it was.The only thing I would mention is it takes a 1 inch socket,which I happened to have, to fit over the end of the FR-5.
Specialized tool to fit 12-spline lockring. I found it helpful to hold it in place by re-inserting quick release skewer before wrenching to keep it from slipping out.
I bought this after I realized that my FR-1 tool would only work with my SRAM lockrings. I figured it was cheaper to buy a second tool and made more sense than replacing all my Shimano lockrings with SRAM models! It works like it's supposed to and the price was great. In fact, the design is better than the SRAM version because the splines are better defined, which results in no slippage.