The new black ceramic rods now feature two grooved sides (on opposite sides of the rod) for more aggressive honing.  Just turn the rod 90° to use the grooved sides or smooth sides.  This 8½" honing rod has a medium (approximately 2000 grit) surface that polishes your edge smooth.  This rod has a steel core with rubber in between to reinforce the rod while providing shock absorption.  The tip has a rubberized plastic end cap to absorb shock and to stabilize the rod against your cutting board when using it.  The black ceramic material is a new type of ceramic that is much harder than traditional white ceramic.  This means it will quickly realign an edge and works well on harder Japanese steel knives which tend to have a higher Rockwell (hardness).