Gridfinity Pen Trays

3u trays work well for thinner writing instruments, such as pencils, thinner pens (nothing thicker than a Pilot Metropolitan/Cocoon - 15.8mm) 4u trays work for most pens, although it would likely be too small for a Namiki Emperor or other overside pens. Calligraphy penholders (e.g., oblique dip nib ones) and glass pens are too long and oddly shaped to use these trays. Gridfinity Rebuilt OpenSCAB Github page