Brass Rigid Motor Shaft Coupling — reliable sleeve adapter for motor transmissions Key benefits Precise shaft connection: rigid, single-piece design provides a direct, stable link between motor and driven shafts for consistent power transfer. Wide compatibility: available in sizes 2mm, 2.3mm, 3mm, 3.17mm, 4mm, 5mm, and 6mm to match common motor shaft diameters. A dedicated 4mm-to-4mm option is included for exact-fit applications. Durable material: machined from brass for corrosion resistance, good wear properties, and lasting mechanical stability in routine use. Easy to use: one-piece construction simplifies installation and reduces alignment complexity compared with multi-part couplings. Function and performance Acts as a rigid transmission joint connector and sleeve adapter for direct motor-to-shaft coupling. Designed to maintain stable alignment under continuous rotation, helping to preserve transmission efficiency and reduce maintenance. Compatibility and sizing Select the coupling size that matches the shaft diameters of your motor and driven component (available sizes: 2mm, 2.3mm, 3mm, 3.17mm, 4mm, 5mm, 6mm). The 4mm-to-4mm option is provided for applications where both mating shafts are 4mm in diameter. Typical applications Hobby and educational robotics: pair small DC or stepper motors to gearboxes, wheels, or encoders for reliable motion. Compact automation and instrumentation: connect precision motors to sensors or small drive assemblies where space and alignment matter. DIY electronics and prototyping: useful for 3D printer upgrades, micro-CNC machines, and other small mechanical projects that require a simple, robust shaft connection. What to expect A single, brass rigid coupling that simplifies motor shaft connections and supports consistent power transmission across compatible shaft sizes.