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Green copper shaft coupler 25 by 10mm with four screws

Unique-Bargains

Unique-Bargains Shaft Coupling 3mm x 3.17mm Green 25x10mm

SKU CH-RCQT-466BY

Connects 3 mm and 3.17 mm motor shafts on RC models, copper construction with four mounting screws included

  • Size or dimensions25 × 10 mm / 0.98 in × 0.39 in (L*D)
  • Connects 3 mm and 3.17 mm motor shafts
  • Copper construction resists corrosion in marine RC models
  • Compact 25 mm length fits tight airframe spaces
  • Green finish simplifies visual inspection during assembly
  • Supplied with four screws for immediate installation

Shaft Coupling for RC Models

This green copper coupling connects a 3 mm motor shaft to a 3.17 mm driven shaft in radio-control airplanes and boats. The 25 mm by 10 mm body fits compact power-train layouts. It is intended for hobbyists building or repairing small electric drive systems.

3 mm to 3.17 mm Bore Adaptation

The coupling bridges the 0.12 inch to 0.12 inch diameter difference between the two shafts, eliminating the need for separate adapters. An M3 thread secures each side with the four included screws. Builders whose shafts match either diameter exactly will not need this part.

Included Mounting Hardware

Four screws ship in the package so the coupler can be installed immediately without sourcing separate fasteners. The hardware matches the M3 thread specification of the coupling body. No additional tools or consumables are mentioned in the data.

How it compares

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

Price $4.99
Cheaper than about 83% of the 2,955 comparable items (median $17.99).

Specifications

Product
Brand nameUnique Bargains
Size & build
Size or dimensions25 × 10 mm / 0.98 in × 0.39 in (L*D)

Questions about this item

How does the 3mm to 3.17mm bore fit on a real motor shaft?

The coupling accepts a 3mm shaft on one side and a 3.17mm shaft on the other, joining two slightly different diameters in a single rigid connector.

What does the M3 thread size cap in practice?

The M3 threads take the four supplied set-screws, locking each shaft securely without needing separate fasteners.

Will the 25mm length and 10mm diameter clear my RC model's bulkhead?

The coupler measures 25mm long by 10mm in diameter, so check that your mounting space allows at least .98 inch by .39 inch.

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