From the product description at the time of purchase: ・Basis weight: 80g/m2 Paper thickness: 0.106mm 500 sheets/ream ・100% plantation pulp (approx. 2.5 kg per ream) ・Compatible with inkjet printers; thick copy paper that prevents ink from bleeding through Compatible with plain paper fax machines, inkjet printers, copiers, and laser printers. A product from a top-class domestic copy paper manufacturer. http://www.app-j.com/topics/info/723.html This is an unopened item from a box purchase (5 reams/box). It was a little too white for my intended use, so I am selling the unopened portion. Thank you.