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Two blue aluminum rigid shaft couplers 25mm long 14mm diameter with M4 screws

Unique-Bargains

Unique-Bargains Rigid Shaft Coupling 4mm-6mm Blue 2pcs

SKU CH-95NS-XJC2J

Connects 4 mm to 6 mm shafts with a 25 mm long, 14 mm diameter aluminium alloy rigid coupler that includes M4 screws

  • Size/Dimensions25 x 14mm / 0.98 inch x 0.55 inch (L*D)
  • Connects 4 mm to 6 mm shafts for flexible motor builds
  • Rigid aluminium alloy body delivers high torque with low inertia
  • Four M4 screws per coupler ensure secure, maintenance-free fastening
  • Compact 25 mm length fits tight mechanical drive spaces
  • Blue anodised finish resists oil and corrosion in model applications

Blue Aluminium Coupler for 4 mm and 6 mm Shafts

This rigid shaft coupling connects a 4 mm shaft to a 6 mm shaft in small mechanical drives. It is made from aluminium alloy to keep inertia low and suits model cars, model boats, moulds and similar light-duty applications.

25 mm Length with 14 mm Outside Diameter

The coupler measures 25 mm long and 14 mm across, providing a compact joint for tight spaces. Its rigid design transmits high torque without a rotation gap, though it cannot accommodate parallel offset between shafts.

Two Couplers and Eight M4 Screws Included

Each pack supplies two blue couplers and eight M4 set screws for immediate assembly. The four-screw pattern on each unit secures both shafts firmly, removing the need to source separate fasteners.

Highlights

  • Connects 4 mm to 6 mm shafts for flexible motor builds
  • Rigid aluminium alloy body delivers high torque with low inertia
  • Four M4 screws per coupler ensure secure, maintenance-free fastening
  • Compact 25 mm length fits tight mechanical drive spaces
  • Blue anodised finish resists oil and corrosion in model applications

Specifications

Size/Dimensions25 x 14mm / 0.98 inch x 0.55 inch (L*D)
BrandUnique Bargains

Questions about this item

Will the 4 mm to 6 mm bore fit the motor and wheel shafts I already use?

The coupler accepts one 4 mm shaft and one 6 mm shaft, so it connects a smaller motor output to a larger driven component without adapters.

How can I confirm the coupling is aligned and transmitting torque after installation?

With 180 degree through-angle and zero rotation gap, the shafts turn together instantly — any visible lag or wobble means the M4 screws need retightening.

Does the package include the fasteners, or must I source M4 screws separately?

The box contains two rigid couplers and eight M4 screws, providing four screws per coupler for immediate assembly.

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