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Two silver aluminum rigid shaft couplers 12mm bore 25mm long 20mm diameter with M4 screws

Unique-Bargains

Unique-Bargains 12mm to 12mm Rigid Coupling L25XD20 Aluminum Alloy 2pcs

SKU CH-KBAB-JHJJT

Connects two 12 mm shafts with a 25 mm long, 20 mm diameter aluminum alloy rigid coupling, supplied as a pair with M4 set screws

  • Connects two 12 mm shafts with zero backlash
  • 25 mm length and 20 mm body fit compact assemblies
  • M4 set screws clamp securely for high torque transfer
  • Aluminium alloy resists oil and corrosion without maintenance
  • Ideal for 3D printers, CNC machines and stepper motors

12mm Rigid Shaft Coupler Set

This pair of aluminum-alloy couplers joins two 12mm shafts with a 25mm overall length and 20mm outside diameter. Each unit uses four M4 set screws for a secure top-tight grip. The rigid design transmits torque without backlash, making it suited to stepper motors, CNC axes, 3D printers and similar precision drives.

Upgrade From Flexible Or Jaw Couplings

Replace a flexible or jaw-type coupler when the application demands zero angular compliance and maximum torsional stiffness. The switch is worthwhile only if the shafts can be aligned to near-perfect concentricity, because the rigid body does not accommodate eccentricity or angular error.

Rigid Coupling Alignment Limits

The coupler permits no measurable eccentricity and effectively zero angular misalignment; shafts must be centred within a fraction of a degree. Any offset loads the screws and shafts with bending forces that accelerate wear or cause sudden failure. Plan for precise mounting fixtures and verify alignment before tightening the M4 hardware.

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 does the 12mm bore rigid coupling fit?

The coupling accepts two 12mm diameter shafts for a direct inline connection.

How are the M4 set screws installed and what is the common mistake?

Insert each M4*4mm screw into the tapped holes and tighten evenly; the error is uneven torque which can misalign the 90-degree screw pattern.

Does the aluminum alloy coupling need lubrication or periodic replacement?

The integrated aluminum alloy body is maintenance-free, oil-proof and corrosion-resistant, so no lubrication or scheduled replacement is required.

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