STAEDTLER Mars Lumochrom 2 mm colour leads in red colour pack of 12 leads. To refill your leadholders with lead at any time, use this Mars carbon 200 box, which contains 12 leads with a line width of 2 mm. These leads are refilled by simply pressing the push-button on the leadholder to open the drop clutch mechanism and inserting the 2 mm lead into the leadholder via the tip.