Get the #1 seller in the world and the industry standard with the Pentel 0.5 mm Lead Refill. The smoothness when writing with it will be obvious. You never need to sharpen the mechanical pencil like the standard lead pencil. Because its proprietary formula resists breaking there s no need stop to clean the lead bits. Select the dark imprint for drawing while the light imprint is used for drafting and template work. It is equivalent to a No. 2 pencil. This pencil lead is guaranteed to accurately scan on tests and documents. Because there 12 in the tube you will have an ample supply.