Kurutoga Replacement Lead for Mechanical Pencils, 0.5mm, HB Discontinued Kurutoga replacement lead. Unopened. [Features] - Sharp and smooth lead - This lead is designed to be sharper and smoother when used with the "Kurutoga" mechanical pencil, which features a unique lead rotation mechanism that keeps the lead sharp. - The outer part of the lead is soft, making it easier to sharpen and write smoothly. - By varying the hardness between the inner and outer parts of the lead, the sharpening ability is improved. - Traditional leads had a structure where the outer part was hard and the inner part was soft. In contrast, Kurutoga replacement lead has a structure where the inner part is hard and the outer part is soft. Therefore, the inner part is resistant to wear, while the outer part wears down easily, resulting in a lead that sharpens easily and writes smoothly.