AinStein Pentel 0.5mm blue leads Approximately 10% stronger than any other lead thanks to its ceramic cell structure. Supplied in tubes with rotating cap easy to dispense. Softer than other refill leads on the market. Suitable for all 0.5 mm mechanical pencils. Available in B grades , 2B, 3B, 4B, HB, H and 2H. 40 mines per tube. Made with 92% recycled material. The percentage is based on the total weight of the product excluding replacement leads.