Selecting the correct bearing requires a balance of load capacity, speed ratings, and environmental resistance. Buyers should prioritize high-carbon chromium steel (GCr15) for standard industrial use due to its high hardness and wear resistance. For high-speed applications, ensure the limiting speed of the bearing exceeds your machine's RPM requirements. Additionally, verify the internal clearance (C2, CN, C3, C4); for instance, C3 clearance is often preferred for high-speed or high-temperature environments to allow for thermal expansion.