My wife liked @Aelyn_1249526's Knitting Counter but didn't want the "U" that was at the bottom so I made a blank version. I also laid the model flat.
Edit 4/19/24: I created an OpenSCAD file that imports “Hex Knitting Counter Blank Bottom.stl” and places the specified letter in the blank area at the bottom.
The author remixed this model.
I removed the shape and letter at the bottom to have it be blank or easier to customize. Created OpenSCAD file to make it easier to add a custom letter. I also laid the model flat.