A common issue with conventional mechanical pencil is that the leads always wear down on one side which results in a wedged tip. However, when the users change their writing position when turning the page for example, they will most probably use a different lead surface. This will sometimes cause dramatic variations in line width. The Uni-ball Kuru Toga Mechanical Pencil resolve this issue by introducing a rotation mechanism which continuously rotates the lead as you write. The spring-empowered clutch rotates the lead very time you left the pencil from the surface, hence madding the lead worn off much more evenly resulting in a more even line width.