We have reached 25 µm because this is the layer resolution on the 3D printers we used, but with other readily available techniques, like CNC or laser etching, it would be possible to reach Z feature sizes below 25 µm. We suggest that scientists interested in filtering and size sorting microfluidic devices move from XY plane features, which are challenging to fabricate via lithography, to Z axis features using simple techniques such as 3D printing, CNC, and laser etching.