Unique-Bargains Rigid Shaft Coupling 4mm-6mm Blue 2pcs
Connects 4 mm to 6 mm shafts with a 25 mm long, 14 mm diameter aluminium alloy rigid coupler that includes M4 screws
- Size or dimensions25 × 14 mm / 0.98 in × 0.55 in (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.
How it compares
Measured against everything we stock in Hose Fittings, Adapters & Clamps, at today’s prices. Recalculated every night.
- Price $5.99
- Cheaper than about 80% of the 2,955 comparable items (median $17.99).
Specifications
| Product | |
|---|---|
| Brand name | Unique Bargains |
| Size & build | |
| Size or dimensions | 25 × 14 mm / 0.98 in × 0.55 in (L*D) |
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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