Normalized tube record

0.370 in OD tube

A measured tube group centered on 0.370-inch outside diameter. It is separated from nominal drill-size classes until a verified equivalence is recorded.

0.370 in OD

Observed outside diameters0.370" (9.4 mm)

Known kit lengths1

Linked kits / projects2

Replacement listings0

Before substituting

Match OD, wall thickness, and length.

The class name helps discovery; it does not override the kit maker's current tube specification. A close drill size does not prove that two brass tubes are interchangeable.

Kit cross-reference

Known barrel lengths

Lucky fountain pen kitsXiamen Rizheng · RZ-FP308Lower / bodybarrel position0.370" (9.4 mm)tube OD1.969" (50.0 mm)tube lengthNot recordedminimum blank cutOpen kit →Lucky rollerball pen kitsXiamen Rizheng · RZ-RP308Lower / bodybarrel position0.370" (9.4 mm)tube OD1.969" (50.0 mm)tube lengthNot recordedminimum blank cutOpen kit →