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Five silver electroplated steel universal joints with wrench and screws

Unique-Bargains

Unique-Bargains 3mm to 3mm Universal Joint Coupling L23 D9 Pack of 5

SKU CH-J564-7A6XV

Pack of five 3 mm universal joints with M3 screws and wrench for connecting shafts in RC models, 3D printers and DIY projects

  • Connects two 3 mm shafts to transmit torque in RC models and DIY projects
  • 45# steel with electroplated finish provides sturdy, durable construction
  • Large transmission torque, high efficiency and stable rotation with small gap impact
  • Pack of five couplings includes M3×0.5 fastening screws and a wrench
  • 23 mm length and 9 mm outer diameter fit compact shaft assemblies

Universal Joint Coupling Pack

This pack contains five silver-tone universal joint couplings designed to link two 3 mm shafts so they rotate together and transmit torque. Each coupling measures 23 mm long with a 9 mm outer diameter and a 3.17 mm by 3 mm inner bore. The units are machined from 45# steel with an electroplated finish and include M3*0.5 fastening screws plus a wrench for installation.

Upgrade From Rigid Couplings

These joints replace fixed or single-piece couplings when shafts are slightly misaligned or when vibration and small gap impacts must be absorbed. The rotatable design allows angular offset while maintaining high transmission efficiency and stable torque delivery. The step up is worthwhile for RC cars, boats, 3D printers, snow blowers, grinders and similar DIY drives that experience shaft movement during operation.

Check Shaft Diameter And Eccentricity

Verify that both shafts measure 3 mm at the coupling point and that the M3*0.5 screws suit your shaft keyways or flats. Confirm the maximum allowable eccentricity for your application so the joint operates within its designed range. Ensure you have space for the 23 mm length and 9 mm diameter on each shaft end before ordering.

How it compares

Measured against everything we stock in Hose Fittings, Adapters & Clamps, at today’s prices. Recalculated every night.

Price $7.99
Cheaper than about 75% of the 2,955 comparable items (median $17.99).

Specifications

Product
Brand nameUnique Bargains

Questions about this item

What shaft diameter fits the 3.17 mm inner bore?

The coupling accepts 3.17 mm and 3 mm shafts, so a 3.17 mm shaft fits directly.

Which step do installers often skip when fitting the two halves?

They forget to align and adjust both shafts within the maximum allowable eccentricity before tightening the M3×0.5 screws.

When should the M3×0.5 fastening screws be checked or replaced?

Inspect the screws after the first few hours of torque transmission and replace any that show thread wear or loosening.

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