... a>drawing disappears in 2-14day accordingly b>one end for write,one end for erasing c>ASTM&EN71+OEM d>opp ... usage range: For tailoring marking on fabric and garment,essential for patternmaking and cutting,fashion design Product advantages,Price,Package & ... shelf timedrawing disappears in 2-14days,according to different material and working conditionQualityStandard:SGS & Intertek test: ASTM D4236,EN71- ...