Review on NTN Bearing 6201ZZ 12 7C3 EM by Adam Rogers

I bought these to rebuild a failed AO Smith 3/4hp fan motor in my oven. The motor shaft is 1/2" and the bearing is easy to fit, but after just a day of use I found that the bearing was completely loose on the shaft and could be moved back and forth by hand! Just for comparison, I later replaced the bearings from another AO Smith motor and they have held on the shaft without any problems ever since. The diameter of the AO Smith shaft is approximately 0.4992.4997", better than that I can measure. and unfortunately I don't have a decent inside micrometer to measure the true inside diameter of these bearings for comparison. The seller must have at least the declared bearing tolerance C3 is not a tolerance, but the bearing clearance of the bearing parts.