This copper alloy traveling nut (also known as a carriage nut) features a mounting flange with four holes threaded for M3 screws. It is intended for use with Tr8×8(P2) leadscrews, which are 8 mm-diameter rods with four independent trapezoidal threads spaced 2 mm apart. One full revolution of such a rod will result in a 8.0 mm linear displacement of the traveling nut.
please note that the nut is not spring loaded, so changes in direction will result in loss of positioning precision due to backlash.
Dimensions
for this nut are shown in the diagram below and are included in the datasheet for the stepper motor with 28cm lead screw, which is available as a . Units are mm.

Pololu Corporation, Pilot Rd. 920, 89119 Las Vegas, Nevada, Vereinigte Staaten, [email protected], https://www.pololu.com/