Lead screw diameter 8mm, length 500mmCopper nut, with 4 holes for fixing to the machineThread: threadScrew pitch: 2mm; Lead: 8mmIf you want higher accuracy, it is recommended to use the anti backlash copper nutSize:T8x8The lead of the thread is 8mm, which means that the nut move 8mm if the nut turns one circle.The advantages of the leadscrew are:Large load carrying capabilityCompactLarge mechanical advantagePrecise and accurate linear motionSmooth, quiet, and low maintenance, very suitable for 3D printer z axis.Minimal number of partsSo this lead screw is very suitable for 3D printer Z axis, such as and Prusa i3.The screw type of this lead screw is thread. Threads are generally stronger than square threads due to their trapezoidal thread profile, which provides greater load-bearing capabilities.colour:Silver + goldMaterial:stainless steelPackage Contents:1 * 500mm lead screw1 * copper nutOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.