... pores 2it is odorless, non-polluting, easy to use, 3 inexpensive and safe Garnet Abrasive1 [pore-forming materials] walnut shell particlesOur ... pores, and it is odorless, non-polluting, easy to use, inexpensive and safe. Moreover, the pore size of the grinding wheel ... .0mm 2.0-4.0mm function:Polishing process of spectecles, jewelry, button, stamping parts, electronic parts, etc.