The Purpose Is To Firmly Connect The Driving Shaft And The Driven Shaft To Rotate Together And Transmit Motion And Torque. So It Can Rotate 360°. Great Suitable For Short Support Shaft, Bushing Model, Miniature Shaft, Model Airplane/ Boat / Car. Jaw Spider Shaft Coupling 6.35mm To 8mm For Stepper Motors at best price in Belgaum Product Summary: Aopin 8mm to 8mm Rotatable Universal Joint Coupling Shaft Stepper Motor, Length 35mm / 1.38", Coupler Connector with Screw for 3D Printer, RC Robot, Car Boat Shaft, DIY Encoder, CNC Machine Metal joints for use in direct-axis motor, motor for the brush motors and small brushless motor ❤Rotatable Universal Joint Coupling Size: 8mm to 8mm / 0., 31 to 0., 31. ❤Coupling Universal Joint Are Used In Servo Motor Systems, 3D Printer, Cnc Machine, Diy Encoder, Spindle Transmissions, Stepping Motors, Lifting Platforms, Machine Tool Transmissions, Stepping Motors, Encoders, Screw Drives, Machine Platforms Or Gearboxes, Etc. The Internal Rollers And Cross Bearings Are Of Fine Workmanship. Especially suitable for medium, high speed and high power transmission., 5., Simple structure, light weight, small size, convenient assembly and disassembly, and no need for lubrication., 42., It can accurately transmit the speed without slip, and can be used for the transmission of precision machinery. Shock Mitigation, Vibration Absorption, High Transmission Efficiency, No Noise, And Low Wear. Calinodesign 6mm To U Joint 2 Section Rotatable Universal Steering... When The Rated Torque Is Exceeded, The Coupling Can Protect The Safety Of The Linkage. CNC Machine Joint Aopin 8mm To 10mm Rigid Coupling Set Screw Shaft Stepper Motor, Length 25mm/1" Motor Coupler Connector Rigid With Screw For 3d Printer Rc Robot Car Model Shaft Cnc Machine Diy Encoder 4pcs Flexible Drive Shaft Coupler