Brahma's Professional line uses the very finest drawing papers available on the planet including Canson, Fabriano and Stonehenge among others.These papers are all imported. The papers are designed for archival value and to make art that is meant to last for hundreds of years. Brahma offers several different Professional lines to meet the most stringent requirements of artists. The Professional line currently in stock uses 180 Gsm Canson drawing paper. This paper is ph7 neutral 100% acid free with a white tint. Due to the thickness of the paper the book is thick.The Brahma book is hand crafted using the finest materials and workmanship. The best quality binding materials are used to make the book very hardy. The book is designed to be light and compact to carry easily. Each book has a pocket inside the back cover.