Bought to replace the rear bearing in the pool pump. The old one started making an awful noise when we launched it this summer. Use a bearing puller to loosen the old one from the shaft and a board and rubber mallet to tap the new one. It's been about three weeks and still nothing. After reading other reviews I removed the dust cover and added some wheel bearing grease before installing. It was already quite a bit there and maybe that would have been nice but I figured a little more wouldn't hurt as I already had it open. The price was right for four packs, so I have three spares on hand.