STAEDTLER Mars Matic Drafting Pen Nibs. Mars Matic Drafting Pen. Resin tip section: POM, Nib: Stainless steel. 750-M013: 0.13mm (ISO). 750-M018: 0.18mm (ISO). 750-M025: 0.25mm (ISO). 58×38×16 mm・11.3g.
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