Bore Diameter d1: 6.35 mm.
Bore Diameter d2: 8 mm.
Also known as : Beam coupling, helical coupling, Flexible coupling.
Aluminium Helical Shaft coupling is commonly used in 3D Printers, CNC machines and other DIY projects to couple Stepper motors and 8MM rods / threaded rods / precision trapezoidal rods. The coupler takes care of small misalignments, deviations and twists in the system.