our core board is mainly used to make high strength chemical fiber tubes, yarn bobbins, industrial paper tubes for paper milling and plastic film ect! The specification of our core board is as following : (1)substance:230g/m2 -600g/m2 (2)rade:F200,F300,F400,F500,F600,F800,FB300,FB500 (3)reel width:80mm-2200mm (4)reel diameter:1100-1150mm (5)packing:wrapped with vinyl film for water proof