The S4 magneto drive end inner race removal tool works in conjunction with a standard bearing puller. The split gripper ring fits behind and around the race and is captured in the puller ring by 2 opposing set screws. A groove on the puller ring provides the point of attachment for the puller arms.
There are precautions that are not included with this puller. Once placed into position, the tabs must be fully seated, by movement of the locking sleeve. This is a problem with bearings that have no spacer, where the bearing race is right up against the magnets. In this case, this tool does not have the ability to grip the race, and you will damage the tool. If the race has a gap, where the tabs lock in, and seat properly, this tool works great. This limitation needs to be noted.
Dont waste your money on this tool. The screws securing the bushing sheared during its first use. I disassembled the tool, rotated the bushing, drilled/tapped new holes and installed hardened steel screws hoping to get at least one use out of this tool. On the second attempt, the teeth gripping the bearing broke off even though the sleeve was installed flush with the end of the tool as the instructions suggest. Just a waste of time and money, especially without the option to return for refund.