2 millimetre is the most common size for clutch pencils (or leadholders). These were much more popular years ago, but there is still a good number of clutch pencils around and there's a good range of 2mm graphite lead available. 2mm lead is roughly equivalent to a typical woodcase graphite pencil. 2mm coloured lead used to widely available but all the well-known manufacturers stopped producing it several years ago. However, we have sourced 2mm coloured lead in blue, red, green, brown, yellow and black from the Czech manufacturer Koh-I-Noor.