Park FR-5 Cassette Lockring Remover Review
The FR-5 and FR-5G from Park Tool are cassette lockring removers, which allow you to remove your cassette lockring so you can replace your cassette.
The FR-5G is a newer model that has a guide on it to hold it steady during cassette removal. (With the FR-5 you have to use the quick release skewer to keep everything in place.)
Pros: As with most Park tools, this one works well. To top things off, the price tag is just $8.
Cons: It does not work on Campagnolo lockrings.
The Final Word
If you need a cassette lockring remover, and you use SRAM or Shimano parts, get one of these. It will last forever and it works like a charm.