... plstic material.16CM length ,3CM height, good quality and promotional gifts for students promotional straight ruler 1. Size: 159*30MM 2 ... available. 6. Certification: EN71 standard.7. The plastic straight ruler is good for draw line straightly and good for school ... 10000PCS. Further more, for stationery, we are not only producing ruler, but we also can manufacture erasers, pencil box..Looking forward ...