This is a 1/4" (6.35mm) spacer for PowerSpec 3D X Dual Extruder Printer, FlashForge Creator Pro, and Creator X with the newer platform so they can use a glass pane on the heated build plate. After I got my 3DX, I realized it did not have the same support platform as the original Creator X that this unit is based on, so I could not use Creator X Z-axis spacers. I noticed some convenient screw locations, so I created this spacer to take advantage of the built-in screw location. There is a 2 degree taper on the vertical slot to help the bottom of the spacer stay tight to the printer's base. You do not really even need to screw it down, but the option is available on the part if you want to. Later I found out that the 3DX Printer uses the same base as the Creator Pro. Therefore, it should fit that model as well, but I do not have a Creator Pro to try it with. Let me know your results and if you find other printers that this Z-axis spacer fits.