T8 8mm Lead 4 Start Lead Screw and Nut for 3D Printer Z Axis (600mm Length) - High Precision Upgrade for Smooth 3D Printing Motion Control

So far these look great. are extremely smooth and come as advertized. The packaging was just a bubble wrap bag with some other bags over the product but they arrived clean and straight. I have yet to install them on my 3d printer but see no reason they will not work great. The time estimate on the tracking was way off. They arrived in about 15 days. They are coming direct from China.