High precision balls are within 10/1,000,000″ round, twice as round as the industry standard, at it’s highest level.52100 High Carbon Chromium Alloy Races:
Vacuum de-gassed process for the purest chromium alloy steel, hardened to R-62, extremely tough and very durable. Polished to a mirror finish for ABEC-3 precision and noiseless movement.
Riveted Steel Retainer for toughness, ABEC-3 tolerances and noise tested, C-3 or C-N Internal Clearance
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