12 CT. 0. 5 MM CERAMICS HIGH-QUALITY MECHANICAL PENCIL LEADS. Fits all 0. 5mm automatic pencil Minimal breakage Available in 0. 5mm, 0. 7mm and 0. 9mm 0. 5mm fine line is ideal for accounting and general writing Produces a smooth, crisp line with dark imprint for easy reading You will never loose the tube's cap with this advance click lead refill dispenser.