Mainly used for metal rods to polish.including: copper rods, stainless steel rods, aluminium rods, sticks, plastic ... metal pipes/rods (working diameter: 1mm-30mm).2 application: copper rods, stainless steel rods, aluminium rods, sticks, plastic round ... rodsincluding: copper rods, stainless steel rods, aluminium rods, sticks, plastic round ...