The Porometer 3G zh is a compact, automatic, very wide size range, low and high flow rate, capillary flow porometer for measuring through-pore sizes using the liquid expulsion technique. The pressure capability of up to 500 psi (the highest of all 3G porometers) allows for pore size distributions in the range of 500 µm down to as small as 18nm to to be measured quickly and reproducibly. The 3G zh's standard configuration of three pressure ranges and two flow rate ranges (with automatic switching between the two) makes this the flagship porometer for research applications both in industry and academia. Its measurement flexibility means that the 3G zh is appropriate for the widest variety of materials, everything from woven textiles and non-woven filter materials, to polymeric membranes, papers, and sintered metals, etc. Gas permeability is a standard capability, liquid permeability is available optionally. The 3G zh conforms to ASTM standard methods D6767, E128, F316, and similar.