These rails are a result of a collaboration effort with CNA and West3D. We went to them and asked them to think of our use case and design their rails specifically for high speed (and high vibration) 3D Printing. This resulted in us selecting a heavier than standard pre-load (a slight reduction in clearance between the rail and the carriage). This should reduce any axis play you may have when using low or no pre-load rails.
We then moved to improve the design aesthetic over what CNA typically ships. This gave us black carriage end caps and added our West3D logo on the carriage in a way that is tasteful and helps break up the traditional matte silver in the carriage block.
Lastly, we said why shouldn't these be stainless steel, I mean that's kind of our thing.
The result are these rails. Rails will be firm, but smooth. These may come pre-lubed with Mobilux EP2.If so, to finish preparation, use a small tipped device (I even used a stick from a sucker) to remove any grease from the rail hole, and then spread it evenly around the rest of the rail using proper rubber gloves. Set the rail on a flat surface, and with light pressure on the carriage move it back and forth a couple dozen times. That's it!