Strong aluminum coupling for connecting your stepper motor to a M5 rod. You can fix the coupling using the hexagonal nuts to the shaft of the stepper motor. Put a M5 nut onto the M5 threaded rod and insert the M5 rod fully into the coupling. Then tighten the M5 nut to fix the rod. You can use grub screws to fasten the coupling to the motor shaft.
Original design and author are available here: http://reprap.org/wiki/Mendel:_Prusa_durable_z-axis_motor_coupling
ReprapWorld is the number one webshop for all your reprap supplies for your 3D printer. We have a large collection of 3D printer components, from our famous electronics lines to filament from our own production. And everything is at a very competitive price!