This is a CNC machined flexible coupling that is ideal for connecting the Z-axis screws to the stepper motors on a Prusa-Mendel i3 Reprap type 3D Printer

One 5mm bore is for the output shaft of a NEMA17 stepper motor and the other 5mm bore is for the M5 threaded rod.

The coupling is made of Aluminium.

Diameter = 19mm
Length = 25mm
Weight = 17g

The price is for 1 coupling.