These are replacement eraser cores for the Mars® plastic 528 holder, supplied two to a blistercard. The holder is the pen-shaped tool with a clip and a core sliding mechanism, and the point of it is precision: a narrow core takes out a single line without touching the work either side of it, which a block eraser cannot do. The cores are the same Mars plastic compound, cut for graphite on paper and matt drafting film, and are phthalate and latex free.

• Eraser core refills for the Mars plastic 528 eraser holder
• For graphite on paper and matt drafting film
• Core sliding mechanism advances the eraser as it wears
• Eraser core refill, article number 528 55
• Phthalate and latex free