These high-quality lead refills always produce smudge-resistant clean marks and sharp lines making them perfect for everything from architectural drafting to school work. Enhancing their value for both busy professionals and students both the leads and erasers are packaged in convenient clear tubes so it"s easy to tell at a glance when more are needed. Lead Degree (Hardness): HB Lead Color: Black Refill(s) For: All Bic Refillable Mechanical Pencils Lead Diameter: 0.5 mm.Unit of Measure : Pack