FR2 — 3.175 × 9.525 × 3.9688 mm

What each manufacturer published.

A dash means that manufacturer did not publish the value. Dimensions every source agrees on are shown above rather than repeated per row.

Where the sources agree.

Where the figures differ, use the drawing from the manufacturer you buy from.

Calculated from the published values.

Arithmetic on the figures above — not a bearing life calculation for your load case.

The works that publish FR2.

Hongchi

Ningbo, Zhejiang, China

Miniature metric, inch and thrust bearings

Ningbo Hongchi manufactures miniature bearings with a published bore range of 1–40 mm. Its product scope includes metric and inch miniature bearings, flanged bearings and flat thrust ball bearings. The company lists miniature motors, cooling fans, drones, instruments and medical equipment among its applications; exact material and closure options should be confirmed per model.

Published ranges: Metric and inch miniature bearings · Flanged miniature bearings · Flat thrust ball bearings

80 designations documented here · 1 reviewed evidence record · source recorded 2026-09-24

Ask Hongchi about FR2

Add to inquiry

Runstar

Zhangzhou, Fujian, China

Miniature ball and thrust bearings

Zhangzhou Runshida manufactures miniature and small deep groove ball bearings and flat thrust ball bearings under the Runstar name. Its published company scope gives a bore range of 1–50 mm and includes nonstandard development. Applications span instruments, small motors, appliances, medical equipment and fishing tackle; dimensions and closures still require model-specific confirmation.

Published ranges: Miniature deep groove ball bearings · Small deep groove ball bearings · Flat thrust ball bearings · Nonstandard miniature designs

223 designations documented here · 1 reviewed evidence record · source recorded 2026-09-24

Ask Runstar about FR2

Add to inquiry

Applications the publishing works state.

Application areas each manufacturer states for its own range. Confirm load, speed, temperature and lubrication for your case.

Not documented by any source here.

Precision class · Internal clearance · Sealing · Material · Cage material · Z class · V class · Dynamic load rating · Static load rating · Limiting speed · Lubrication · Operating temperature · Precision standard · Ring material · Rolling element material · Limiting speed — grease · Limiting speed — oil · Noise / vibration test method · Manufacturer series · Manufacturer suffix · Ball count · Ball diameter.

Ask the manufacturer for these when you enquire.

Other designations with the same 3.175x9.525x3.9688 mm envelope.

Same envelope, but sealing, internal design, clearance and load capability differ — not interchangeable by default.