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

Unique-Bargains

Unique-Bargains Shaft Coupling 4mm-8mm Bore L25xD14 Blue 2PCS

SKU CH-VVP4-3V1SR

Connects 4 mm to 8 mm shafts with an aluminum rigid coupler measuring 25 mm long and 14 mm wide, supplied in a blue two-pack with eight M4 screws

  • Size/Dimensions25 x 14mm / 0.98 inch x 0.55 inch (L*D)
  • Connects 4 mm to 8 mm shafts for flexible builds
  • Rigid aluminium alloy design delivers high torque with low inertia
  • Zero backlash ensures precise motion in models and machines
  • Maintenance-free, oil-proof and corrosion-resistant for long service
  • Includes eight M4 screws for quick, secure installation

Rigid Shaft Coupler 4-8 mm Bore

This aluminium alloy rigid coupler joins a 4 mm shaft to an 8 mm shaft with zero backlash. Each piece measures 25 mm long and 14 mm in outside diameter. The blue anodised finish resists oil and corrosion. Two couplers and eight M4 screws are supplied in the pack.

Suits hobby drives needing exact alignment

Model car, boat and light mechanical builders who require a maintenance-free, high-torque link will benefit. Users needing flexible misalignment compensation or a different bore combination should select another coupling style.

4 mm to 8 mm connection diameter decides fit

The single critical specification is the stepped bore that accepts 4 mm on one end and 8 mm on the other. If your shafts do not match those exact diameters this coupler cannot be used.

Highlights

  • Connects 4 mm to 8 mm shafts for flexible builds
  • Rigid aluminium alloy design delivers high torque with low inertia
  • Zero backlash ensures precise motion in models and machines
  • Maintenance-free, oil-proof and corrosion-resistant for long service
  • Includes eight M4 screws for quick, secure installation

Specifications

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

Questions about this item

Will the M4 set screws on this 25 mm long aluminium coupling need periodic re-tightening?

The coupling is described as maintenance-free, so the eight M4 screws should not require routine adjustment once installed correctly.

What misalignment can the rigid 14 mm diameter coupler tolerate before binding occurs?

The design allows up to 180 degree angular compensation through elastic action, eliminating rotation gap within that limit.

Does the aluminium alloy body stay cool during continuous all-day operation?

Aluminium alloy construction reduces inertia and dissipates heat efficiently, keeping temperature rise minimal under sustained use.

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