Review on 🔩 PGN 0.09375 Chrome Bearing: Unmatched Precision for Optimal Performance by Rob Madden

They actually measure 2.37-2.38mm correctly with a Mitutoyo caliper. Cheap Chinese linear rails use 2.33-2.37 balls depending on how worn/calculated their tools are when machining the rails. Use them for a great glide after the original rails and balls wear out and sag. These are great balls, but they will mess with cheap off-the-shelf parts waiting for tight tolerances.