100 1/4 inch Diameter Stainless Steel 440C G16 Bearing Balls

Good company; delivers as promised

i used these to replace the original nylon bearings in a Celestron telescope that was equatorially mounted which placed stress on the original bearings leading to them warping which in turn made the mount unstable and unable to be precise in it's "GoTo" commands. The new bearings function flawlessly and won't be subject to the warpage!