Hi s.sculella,
The lead error is ± .006 inch/ft.
Repeatability is a system feature and not part of any screw or nut spec. It is a function of the load, bearings, mountings, coupling, gearbox or drive train, motor, controller, feedback device, operating conditions, etc….in addition to the screw and nut.
Typically users build the positioning system and then measure the repeatability at intervals during life testing conducted at rated loads and operating conditions.
Thank you for using our products, and let us know if we can provide more information.