These 4 pictures will assist you in understanding 'Nano'. Mesh is a standardized method for measuring the size of a particle. The dark squares in the above pictures show the different sizes of 4 meshes, 100 meshes, 900 meshes and 2,500 meshes respectively. Our skin pore accepts at least 2,400 meshes, our Nano Pearl Powder are 180,000 meshes, it is very easy for us to absorb. Well, 'Nano' is short for nanometer, it is a measurement of a particle, 1nm equals 1 billionth of 1 meter (0.0000000001 meter).