These bearing extractors grip the inside race of a sealed bearing, allowing the bearing to be tapped out of the hub shell or frame component. Insert the extractor into the bearing, tighten one side with a matching wrench, and the collet expands to grip the inside of the bearing. Tap the extractor & bearing out together with a punch and hammer.
All extractors are size specific! If attempting to remove a bearing of a different size than the extractor, you will permanently damage or break the extractor. If the extractor is smaller than the bearing, try using a shim between the extractor and the bearing to get the tightest fit before tightening the extractor bolt.