3 mm diameter lead core (+/-5%)
Made of non-toxic colour pigments and binding components (wax, resin, etc)
The composition of the lead should be strong and enable fine, smooth and consistent writing
Writing should cause no damage (scratches) to the writing surface
The lead should be glued onto the pencil shaft to avoid movement and be centered along the length of the pencil, it should not break off during sharpening
Does not contain lead (Pb) and the content of other heavy metals in lead core must be lower than relevant standards (ASTM D4236 standards or EN71, part 3) |