The Uni Nano Dia Colour Erasable refill Lead 0.5 mm can refill most of the standard 0.5mm mechanical pencils. This refill lead is available in 7 vivid colours, i.e. Red, Pink, Orange, Lavender, Blue, Mint Blue, and Green. You can purchase each single colour on its own or you can buy the pre-mixed colour set. Each box contains 20 refill leads.