When I ordered these bearings for my manufacturing plant, I wasn't quite sure what to expect from them. But after trying them out, I'm incredibly impressed. They have a great quality build and provide exceptional performance, which is crucial in our industrial and scientific environment. The shields do an excellent job keeping contaminates out, prolonging the life of the bearings. However, they can be slightly more expensive than some other options on the market. Overall, I highly recommend these bearings to anyone in need of high-quality bearings for their power transmission products.