Blocks are glued on 4 sides. A professional-grade paper. This economical, high quality paper is perfect for the students of fine arts schools and beginners & emerging artist. It is constructed of 25% cotton and lignin-free cellulose, with a cold press surface. It is acid free, and internally and externally sized. Ideal for watercolour, tempera, gouache, acrylic, ink and drawing. 200 GSM Contains 20 Sheets.