1mm position accuracy for timing belt

[motomage]

Surely the position accuracy is not so much a function of the belt but more to do with the stepper motor angular movement ? or whatever is driving the belt.
Also you don't say where the required accuracy has to be measured ? belt position, driven ball screw, item connected to ball screw via ball nut, etc.

hi eddy, thanks for replying.
What do you mean by the stepper motor angular movement ??

By position accuracy i meant the motion accuracy and reliability of the belt position.